fs_mknod_as.hpp

* Provides: slight improvement in performance as it no longer will
need to find and then act on the files.
* It doesn't make sense to support all original policy types. Most
people used 'newest' or 'ff' and 'combine' is a better default which
has same runtime as 'newest' but with better output.

.cirrus.yml

@@ -1,150 +0,0 @@
-linux_task:
-  name: "alpine:latest"
-  container:
-    image: alpine:latest
-    cpu: 4
-    memory: 4G
-  timeout_in: 15m
-  script:
-    - buildtools/install-build-pkgs
-    - make STATIC=1 LTO=1
-
-linux_task:
-  name: "alpine-arm:latest"
-  arm_container:
-    image: alpine:latest
-    cpu: 4
-    memory: 4G
-  timeout_in: 15m
-  script:
-    - buildtools/install-build-pkgs
-    - make STATIC=1 LTO=1
-
-linux_task:
-  name: "fedora:41"
-  container:
-    image: fedora:41
-    cpu: 4
-    memory: 4G
-  timeout_in: 15m
-  script:
-    - buildtools/install-build-pkgs
-    - make
-    - make rpm
-
-linux_task:
-  name: "fedora-arm:41"
-  arm_container:
-    image: fedora:41
-    cpu: 4
-    memory: 4G
-  timeout_in: 15m
-  script:
-    - buildtools/install-build-pkgs
-    - make
-    - make rpm
-
-linux_task:
-  name: "ubuntu:22.04"
-  container:
-    image: ubuntu:22.04
-    cpu: 4
-    memory: 4G
-  timeout_in: 15m
-  script:
-    - buildtools/install-build-pkgs
-    - git fetch
-    - make deb
-    - apt-get -y install fuse
-    - dpkg -i ../*.deb
-    - mergerfs -v || true
-
-linux_task:
-  name: "ubuntu:24.04"
-  container:
-    image: ubuntu:24.04
-    cpu: 4
-    memory: 4G
-  timeout_in: 15m
-  script:
-    - buildtools/install-build-pkgs
-    - git fetch
-    - make deb
-    - apt-get -y install fuse
-    - dpkg -i ../*.deb
-    - mergerfs -v || true
-
-linux_task:
-  name: "ubuntu:latest"
-  container:
-    image: ubuntu:latest
-    cpu: 4
-    memory: 4G
-  timeout_in: 15m
-  script:
-    - buildtools/install-build-pkgs
-    - git fetch
-    - make deb
-    - apt-get -y install fuse
-    - dpkg -i ../*.deb
-    - mergerfs -v || true
-
-linux_task:
-  name: "ubuntu-arm:latest"
-  arm_container:
-    image: ubuntu:latest
-    cpu: 4
-    memory: 4G
-  timeout_in: 15m
-  script:
-    - buildtools/install-build-pkgs
-    - git fetch
-    - make deb
-    - apt-get -y install fuse
-    - dpkg -i ../*.deb
-    - mergerfs -v || true
-
-linux_task:
-  name: "debian:12"
-  container:
-    image: debian:12
-    cpu: 4
-    memory: 4G
-  timeout_in: 15m
-  script:
-    - buildtools/install-build-pkgs
-    - git fetch
-    - make deb
-    - apt-get -y install fuse
-    - dpkg -i ../*.deb
-    - mergerfs -v || true
-
-linux_task:
-  name: "debian:latest"
-  container:
-    image: debian:latest
-    cpu: 4
-    memory: 4G
-  timeout_in: 15m
-  script:
-    - buildtools/install-build-pkgs
-    - git fetch
-    - make deb
-    - apt-get -y install fuse
-    - dpkg -i ../*.deb
-    - mergerfs -v || true
-
-linux_task:
-  name: "debian-arm:latest"
-  arm_container:
-    image: debian:latest
-    cpu: 4
-    memory: 4G
-  timeout_in: 15m
-  script:
-    - buildtools/install-build-pkgs
-    - git fetch
-    - make deb
-    - apt-get -y install fuse
-    - dpkg -i ../*.deb
-    - mergerfs -v || true

.github/ISSUE_TEMPLATE/bug_report.md

@@ -7,22 +7,31 @@ assignees: ''
 
 ---
 
+See also https://trapexit.github.io/mergerfs/latest/support
+
 **Describe the bug**
 
 A clear and concise description of the unexpected behavior.
 
-**Please be sure to use latest release of mergerfs to ensure the issue still exists. Not your distro's latest but the latest official release.**
+**Please be sure to use latest release of mergerfs to ensure the issue
+still exists. Not your distro's latest but the latest official
+release. Support will NOT be provided for old versions.**
 
-The master branch is **not** to be considered production ready. Feel free to file bug reports but do so indicating clearly that you are testing unreleased code.
+The `master` branch is **not** to be considered production ready. Feel
+free to file bug reports but do so indicating clearly that you are
+testing unreleased code.
 
 
 **To Reproduce**
 
-Steps to reproduce the behavior. List **all** steps to reproduce. **All** settings.
+Provide steps to reproduce the behavior. List **all** steps to
+reproduce. **All** settings. The version of all software involved.
 
 Please simplify the reproduction as much as possible.
- - Unless it is dependenat on multiple branches, use a single branch
- - Reproduce with standard tooling if possible (touch,truncate,rm,rmdir,ln,etc.) Having to install 3rd party software will make debugging more difficult.
+ * Unless it is dependenat on multiple branches, use a single branch
+ * Reproduce with standard tooling if possible
+   (touch,truncate,rm,rmdir,ln,etc.) Having to install 3rd party
+   software will make debugging more difficult.
 
 
 **Expected behavior**
@@ -30,19 +39,38 @@ Please simplify the reproduction as much as possible.
 A clear and concise description of the expected behavior.
 
 
+**Workarounds already tested**
+
+Please list all workarounds attempted and why they were ruled out as
+options.
+
+
 **System information:**
 
- - OS, kernel version: `uname -a`
- - mergerfs version: `mergerfs -V`
- - mergerfs settings
- - List of drives, filesystems, & sizes:
-   - `df -h`
-   - `lsblk -f`
- - A strace of the application having a problem:
-   - `strace -fvTtt -s 256 -o /tmp/app.strace.txt <cmd>`
-   - `strace -fvTtt -s 256 -o /tmp/app.strace.txt -p <appPID>`
- - strace of mergerfs while app tried to do it's thing:
-   - `strace -fvTtt -s 256 -p <mergerfsPID> -o /tmp/mergerfs.strace.txt`
+ * Attach output from
+   [mergerfs.collect-info](https://trapexit.github.io/mergerfs/latest/tooling/#mergerfscollect-info)
+   tool.
+ * Alternatively:
+   * OS: `lsb_release -a`
+   * kernel version: `uname -a`
+   * mergerfs version: `mergerfs --version`
+   * mergerfs settings / arguments: from fstab, systemd unit, command
+     line, OMV plugin, etc.
+   * List of drives, filesystems, & sizes:
+     * `df -h`
+     * `lsblk -o NAME,FSTYPE,FSSIZE,SIZE,MOUNTPOINTS,RM,RO,ROTA`
+   * All information about the relevant paths and files: permissions,
+     ownership, etc.
+   * All information about the application making the requests:
+     version, uid/gid
+ * Is mergerfs running within a container or used with container
+   technologies?
+ * Are the client apps using mergerfs running in a container?
+ * A strace of the application having a problem:
+   * `strace -fvTtt -s 256 -o /tmp/app.strace.txt <cmd>`
+   * `strace -fvTtt -s 256 -o /tmp/app.strace.txt -p <appPID>`
+ * strace of mergerfs while app tried to do it's thing:
+   * `strace -fvTtt -s 256 -p <mergerfsPID> -o /tmp/mergerfs.strace.txt`
 
 **Additional context**
 

.github/workflows/codeql.yml

@@ -1,42 +0,0 @@
-name: "CodeQL"
-
-on:
-  push:
-    branches: [ "master" ]
-  pull_request:
-    branches: [ "master" ]
-  schedule:
-    - cron: "7 3 * * 6"
-
-jobs:
-  analyze:
-    name: Analyze
-    runs-on: ubuntu-latest
-    permissions:
-      actions: read
-      contents: read
-      security-events: write
-
-    strategy:
-      fail-fast: false
-      matrix:
-        language: [ python, cpp ]
-
-    steps:
-      - name: Checkout
-        uses: actions/checkout@v3
-
-      - name: Initialize CodeQL
-        uses: github/codeql-action/init@v2
-        with:
-          languages: ${{ matrix.language }}
-          queries: +security-and-quality
-
-      - name: Autobuild
-        uses: github/codeql-action/autobuild@v2
-        if: ${{ matrix.language == 'python' || matrix.language == 'cpp' }}
-
-      - name: Perform CodeQL Analysis
-        uses: github/codeql-action/analyze@v2
-        with:
-          category: "/language:${{ matrix.language }}"

.github/workflows/mkdocs.yml

@@ -29,7 +29,7 @@ jobs:
       - name: Install dependencies
         working-directory: ./mkdocs
         run: |
-          pip install --no-cache-dir mkdocs mkdocs-material pymdown-extensions mike
+          ./build-venv
 
       - name: Deploy docs
         working-directory: ./mkdocs
@@ -37,13 +37,4 @@ jobs:
           REF_TYPE: ${{ github.ref_type }}
           REF_NAME: ${{ github.ref_name }}
         run: |
-          if [ "$REF_TYPE" = "tag" ]; then
-            mike deploy "$REF_NAME" "latest" --allow-empty --ignore-remote-status --update-aliases
-            mike set-default "latest"
-            #git checkout gh-pages
-            #git push -f origin gh-pages
-          elif [ "$REF_TYPE" = "branch" ] && [ "$REF_NAME" = "master" ]; then
-            mike deploy "master" --ignore-remote-status --allow-empty
-            #git checkout gh-pages
-            #git push -f origin gh-pages
-          fi
+          ./generate-and-push-docs

Makefile

@@ -12,6 +12,8 @@
 #  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 #  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 
+$(info mergerfs MAKEFLAGS: $(MAKEFLAGS))
+
 ifeq ($(shell id -u),0)
 FAKEROOT ?=
 endif
@@ -34,6 +36,7 @@ TOUCH 	  ?= touch
 
 BUILDDIR := build
 GITHUB_REPO ?= "https://github.com/trapexit/mergerfs"
+RELEASE_SAMPLE ?= "debian:13.amd64"
 
 ifndef GIT_REPO
 ifneq ($(shell $(GIT) --version 2> /dev/null),)
@@ -49,7 +52,21 @@ UGID_USE_RWLOCK ?= 0
 ifdef NDEBUG
 OPT_FLAGS := -O2 -DNDEBUG
 else
-OPT_FLAGS := -O0 -g -fno-omit-frame-pointer -DDEBUG
+ifdef SANITIZE
+ifeq ($(SANITIZE),1)
+  override SANITIZE := -fsanitize=address,undefined,leak
+else
+  override SANITIZE := -fsanitize=$(SANITIZE)
+endif
+endif
+OPT_FLAGS := -O0 \
+	     -g \
+	     -fno-omit-frame-pointer \
+	     $(SANITIZE) \
+	     -fstack-protector-strong \
+             -Wextra \
+	     -Wno-unused-parameter \
+             -DDEBUG
 endif
 
 ifdef STATIC
@@ -172,7 +189,7 @@ $(BUILDDIR)/tests: $(BUILDDIR)/mergerfs $(TESTS_OBJS)
 .PHONY: libfuse
 $(LIBFUSE):
 libfuse:
-	$(MAKE) NDEBUG=$(NDEBUG) -C libfuse
+	$(MAKE) -C libfuse
 
 tests: $(BUILDDIR)/tests
 
@@ -276,6 +293,10 @@ ifdef GIT_REPO
 	$(GIT2DEBCL) --name mergerfs > debian/changelog
 else
 	$(CP) -v ChangeLog debian/changelog
+	$(eval DISTRO := $(shell lsb_release -i -s | tr '[:upper:]' '[:lower:]'))
+	$(eval CODENAME := $(shell lsb_release -c -s | tr '[:upper:]' '[:lower:]'))
+	sed -i 's/~unknown-unknown/~$(DISTRO)-$(CODENAME)/g' debian/changelog
+	sed -i 's/ unknown; / $(CODENAME); /g' debian/changelog
 endif
 
 .PHONY: signed-deb
@@ -318,6 +339,7 @@ install-build-tools:
 
 define build_release
 	$(eval GITREF ?= $(shell git describe --exact-match --tags HEAD 2>/dev/null || git symbolic-ref --short HEAD 2>/dev/null || git rev-parse --short HEAD))
+	@echo "GITREF=$(GITREF)"
 	./buildtools/build-release \
 		--target=$(1) \
 		$(if $(CLEANUP),--cleanup) \
@@ -332,7 +354,7 @@ endef
 release:
 	$(call build_release,"all")
 release-sample:
-	$(call build_release,"debian:13.amd64")
+	$(call build_release,$(RELEASE_SAMPLE))
 release-amd64:
 	$(call build_release,"amd64")
 release-arm64:
@@ -346,6 +368,11 @@ release-static:
 release-tarball:
 	$(call build_release,"tarball")
 
+container:
+	$(eval GITREF ?= $(shell git describe --exact-match --tags HEAD 2>/dev/null || git symbolic-ref --short HEAD 2>/dev/null || git rev-parse --short HEAD))
+	@echo "GITREF=$(GITREF)"
+	./buildtools/build-containerimage "$(GITREF)"
+
 .PHONY: tags
 tags:
 	rm -fv TAGS

README.md

@@ -25,7 +25,7 @@ etc.](https://trapexit.github.io/mergerfs/latest/project_comparisons/)
 * Works with filesystems of [almost any
   type](https://trapexit.github.io/mergerfs/latest/faq/compatibility_and_integration/#what-filesystems-can-be-used-as-branches)
 * Ignore read-only filesystems when creating files
-* [Hard links](https://trapexit.github.io/mergerfs/preview/faq/technical_behavior_and_limitations/#do-hard-links-work)
+* [Hard links](https://trapexit.github.io/mergerfs/latest/faq/technical_behavior_and_limitations/#do-hard-links-work)
 * Hard link [copy-on-write /
   CoW](https://trapexit.github.io/mergerfs/latest/config/link_cow/)
 * [Runtime configurable](https://trapexit.github.io/mergerfs/latest/runtime_interface/)

buildtools/build-containerimage

@@ -0,0 +1,16 @@
+#!/bin/sh
+
+GIT_BRANCH="${1:-master}"
+
+set -x
+podman \
+    build \
+    --squash \
+    --no-cache \
+    --force-rm \
+    --build-arg="GIT_REPO=file:///mnt" \
+    --build-arg="BRANCH=${GIT_BRANCH}" \
+    -v "${PWD}":/mnt:ro \
+    -f "buildtools/containerimage/Containerfile" \
+    --tag "ghcr.io/trapexit/mergerfs:${GIT_BRANCH}" \
+    buildtools/

buildtools/build-release

@@ -19,7 +19,7 @@ def build(git_repo,
     if os.path.exists(git_repo):
         git_repo = os.path.realpath(git_repo)
         args += ['-v',f'{git_repo}:/tmp/mergerfs.git:ro']
-        args += ['--build-arg=GIT_REPO=/tmp/mergerfs.git']
+        args += ['--build-arg=GIT_REPO=file:///tmp/mergerfs.git']
     else:
         args += [f'--build-arg=GIT_REPO={git_repo}']
     args += ['-o',pkgdirpath,

buildtools/containerfiles/static.amd64

@@ -1,13 +1,15 @@
-ARG BUILD_TIMESTAMP=0
 FROM --platform=linux/amd64 alpine:latest as build
 COPY install-build-pkgs /tmp/
 RUN /tmp/install-build-pkgs
-ARG BRANCH=master
-RUN git clone --single-branch --depth=1 https://github.com/trapexit/mergerfs /tmp/mergerfs --branch="${BRANCH}"
+ARG BUILD_TIMESTAMP=0
+ARG GIT_REPO
+ARG BRANCH
+RUN git clone --single-branch --branch="${BRANCH}" ${GIT_REPO} /tmp/mergerfs 
 WORKDIR /tmp/mergerfs
 RUN make NDEBUG=1 LTO=1 STATIC=1 DESTDIR=/tmp -j$(nproc) install
 RUN mkdir /build
-RUN tar cvfz /build/mergerfs-static-linux_amd64.tar.gz --directory=/tmp usr sbin
+RUN /tmp/usr/local/bin/mergerfs --version | head -n1 | cut -c 11- | tee /tmp/version
+RUN tar cvfz /build/mergerfs-$(cat /tmp/version)-static-linux_amd64.tar.gz --directory=/tmp usr sbin
 
 FROM scratch
 COPY --from=build /build/ /

buildtools/containerfiles/static.arm64

@@ -1,13 +1,15 @@
-ARG BUILD_TIMESTAMP=0
 FROM --platform=linux/arm64 alpine:latest as build
 COPY install-build-pkgs /tmp/
 RUN /tmp/install-build-pkgs
-ARG BRANCH=master
-RUN git clone --single-branch --depth=1 https://github.com/trapexit/mergerfs /tmp/mergerfs --branch="${BRANCH}"
+ARG BUILD_TIMESTAMP=0
+ARG GIT_REPO
+ARG BRANCH
+RUN git clone --single-branch --branch="${BRANCH}" ${GIT_REPO} /tmp/mergerfs 
 WORKDIR /tmp/mergerfs
 RUN make NDEBUG=1 LTO=1 STATIC=1 DESTDIR=/tmp -j$(nproc) install
 RUN mkdir /build
-RUN tar cvfz /build/mergerfs-static-linux_arm64.tar.gz --directory=/tmp usr sbin
+RUN /tmp/usr/local/bin/mergerfs --version | head -n1 | cut -c 11- | tee /tmp/version
+RUN tar cvfz /build/mergerfs-$(cat /tmp/version)-static-linux_arm64.tar.gz --directory=/tmp usr sbin
 
 FROM scratch
 COPY --from=build /build/ /

buildtools/containerfiles/static.armhf

@@ -1,13 +1,15 @@
-ARG BUILD_TIMESTAMP=0
 FROM --platform=linux/armhf alpine:latest as build
 COPY install-build-pkgs /tmp/
 RUN /tmp/install-build-pkgs
-ARG BRANCH=master
-RUN git clone --single-branch --depth=1 https://github.com/trapexit/mergerfs /tmp/mergerfs --branch="${BRANCH}"
+ARG BUILD_TIMESTAMP=0
+ARG GIT_REPO
+ARG BRANCH
+RUN git clone --single-branch --branch="${BRANCH}" ${GIT_REPO} /tmp/mergerfs 
 WORKDIR /tmp/mergerfs
 RUN make NDEBUG=1 LTO=1 STATIC=1 DESTDIR=/tmp -j$(nproc) install
 RUN mkdir /build
-RUN tar cvfz /build/mergerfs-static-linux_armhf.tar.gz --directory=/tmp usr sbin
+RUN /tmp/usr/local/bin/mergerfs --version | head -n1 | cut -c 11- | tee /tmp/version
+RUN tar cvfz /build/mergerfs-$(cat /tmp/version)-static-linux_armhf.tar.gz --directory=/tmp usr sbin
 
 FROM scratch
 COPY --from=build /build/ /

buildtools/containerfiles/static.i386

@@ -1,13 +1,15 @@
-ARG BUILD_TIMESTAMP=0
 FROM --platform=linux/i386 alpine:latest as build
 COPY install-build-pkgs /tmp/
 RUN /tmp/install-build-pkgs
-ARG BRANCH=master
-RUN git clone --single-branch --depth=1 https://github.com/trapexit/mergerfs /tmp/mergerfs --branch="${BRANCH}"
+ARG BUILD_TIMESTAMP=0
+ARG GIT_REPO
+ARG BRANCH
+RUN git clone --single-branch --branch="${BRANCH}" ${GIT_REPO} /tmp/mergerfs 
 WORKDIR /tmp/mergerfs
 RUN make NDEBUG=1 LTO=1 STATIC=1 DESTDIR=/tmp -j$(nproc) install
 RUN mkdir /build
-RUN tar cvfz /build/mergerfs-static-linux_i386.tar.gz --directory=/tmp usr sbin
+RUN /tmp/usr/local/bin/mergerfs --version | head -n1 | cut -c 11- | tee /tmp/version
+RUN tar cvfz /build/mergerfs-$(cat /tmp/version)-static-linux_i386.tar.gz --directory=/tmp usr sbin
 
 FROM scratch
 COPY --from=build /build/ /

buildtools/containerfiles/static.riscv64

@@ -1,13 +1,15 @@
-ARG BUILD_TIMESTAMP=0
 FROM --platform=linux/riscv64 alpine:latest as build
 COPY install-build-pkgs /tmp/
 RUN /tmp/install-build-pkgs
-ARG BRANCH=master
-RUN git clone --single-branch --depth=1 https://github.com/trapexit/mergerfs /tmp/mergerfs --branch="${BRANCH}"
+ARG BUILD_TIMESTAMP=0
+ARG GIT_REPO
+ARG BRANCH
+RUN git clone --single-branch --branch="${BRANCH}" ${GIT_REPO} /tmp/mergerfs 
 WORKDIR /tmp/mergerfs
 RUN make NDEBUG=1 LTO=1 STATIC=1 DESTDIR=/tmp -j$(nproc) install
 RUN mkdir /build
-RUN tar cvfz /build/mergerfs-static-linux_riscv64.tar.gz --directory=/tmp usr sbin
+RUN /tmp/usr/local/bin/mergerfs --version | head -n1 | cut -c 11- | tee /tmp/version
+RUN tar cvfz /build/mergerfs-$(cat /tmp/version)-static-linux_riscv64.tar.gz --directory=/tmp usr sbin
 
 FROM scratch
 COPY --from=build /build/ /

buildtools/containerfiles/tarball

@@ -1,13 +1,17 @@
-ARG BUILD_TIMESTAMP=0
 FROM alpine:latest as tarball
+
 COPY install-build-pkgs /tmp/
 RUN /tmp/install-build-pkgs
+
+ARG BUILD_TIMESTAMP=0
 ARG BRANCH=master
-RUN git clone --single-branch --depth=1 https://github.com/trapexit/mergerfs /tmp/mergerfs --branch="${BRANCH}"
+ARG GIT_REPO
+
+RUN git clone --single-branch "${GIT_REPO}" /tmp/mergerfs --branch="${BRANCH}"
 RUN cd /tmp/mergerfs && make version tarball
+
 RUN mkdir /build
 RUN cp -v /tmp/mergerfs/*.tar.gz /build/
 
-
 FROM scratch
 COPY --from=tarball /build/ /

buildtools/containerfiles/ubuntu:25.10.amd64

@@ -0,0 +1,10 @@
+FROM --platform=amd64 ubuntu:25.10 as build
+COPY install-build-pkgs build-mergerfs /tmp/
+RUN /tmp/install-build-pkgs
+ARG BUILD_TIMESTAMP=0
+ARG GIT_REPO
+ARG BRANCH
+RUN /tmp/build-mergerfs $GIT_REPO $BRANCH
+
+FROM scratch
+COPY --from=build /build/ /

buildtools/containerfiles/ubuntu:25.10.arm64

@@ -0,0 +1,10 @@
+FROM --platform=arm64 ubuntu:25.10 as build
+COPY install-build-pkgs build-mergerfs /tmp/
+RUN /tmp/install-build-pkgs
+ARG BUILD_TIMESTAMP=0
+ARG GIT_REPO
+ARG BRANCH
+RUN /tmp/build-mergerfs $GIT_REPO $BRANCH
+
+FROM scratch
+COPY --from=build /build/ /

buildtools/containerfiles/ubuntu:25.10.armhf

@@ -0,0 +1,10 @@
+FROM --platform=armhf ubuntu:25.10 as build
+COPY install-build-pkgs build-mergerfs /tmp/
+RUN /tmp/install-build-pkgs
+ARG BUILD_TIMESTAMP=0
+ARG GIT_REPO
+ARG BRANCH
+RUN /tmp/build-mergerfs $GIT_REPO $BRANCH
+
+FROM scratch
+COPY --from=build /build/ /

buildtools/containerfiles/ubuntu:25.10.riscv64

@@ -0,0 +1,10 @@
+FROM --platform=riscv64 ubuntu:25.10 as build
+COPY install-build-pkgs build-mergerfs /tmp/
+RUN /tmp/install-build-pkgs
+ARG BUILD_TIMESTAMP=0
+ARG GIT_REPO
+ARG BRANCH
+RUN /tmp/build-mergerfs $GIT_REPO $BRANCH
+
+FROM scratch
+COPY --from=build /build/ /

buildtools/containerimage/Containerfile

@@ -0,0 +1,19 @@
+FROM --platform=linux/amd64 alpine:latest as build
+
+ARG GIT_REPO
+ARG BRANCH
+
+RUN <<EOF
+    apk add git gcc g++ make linux-headers
+    git clone --single-branch --branch="${BRANCH}" "${GIT_REPO}" /tmp/mergerfs
+    cd /tmp/mergerfs
+    make NDEBUG=1 LTO=1 STATIC=1 DESTDIR=/tmp/install -j$(nproc) install
+    tar cvfz /tmp/mergerfs.tgz --directory=/tmp/install usr sbin
+EOF
+
+FROM --platform=linux/amd64 alpine:latest
+RUN --mount=from=build,source=/tmp/mergerfs.tgz,target=/tmp/mergerfs.tgz <<EOF
+    tar xvf /tmp/mergerfs.tgz -C /
+EOF
+ENTRYPOINT ["/usr/local/bin/mergerfs"]
+CMD ["--help"]

libfuse/Makefile

@@ -12,6 +12,8 @@
 #  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 #  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 
+$(info libfuse MAKEFLAGS: $(MAKEFLAGS))
+
 AR      ?= ar
 CHMOD   ?= chmod
 CHOWN   ?= chown
@@ -33,7 +35,22 @@ endif
 ifeq ($(NDEBUG),1)
 OPT_FLAGS := -O2 -DNDEBUG
 else
-OPT_FLAGS := -O0 -g -DDEBUG -fno-omit-frame-pointer
+ifdef SANITIZE
+ifeq ($(SANITIZE),1)
+  override SANITIZE := -fsanitize=address,undefined,leak
+else
+  override SANITIZE := -fsanitize=$(SANITIZE)
+endif
+endif
+OPT_FLAGS := -O0 \
+	     -g \
+	     -fno-omit-frame-pointer \
+	     $(SANITIZE) \
+	     -fstack-protector-strong \
+             -Wextra \
+	     -Werror \
+	     -Wno-unused-parameter \
+             -DDEBUG
 endif
 
 ifeq ($(LTO),1)
@@ -60,7 +77,6 @@ INSTALLMAN1DIR ?= $(DESTDIR)$(MAN1DIR)
 BUILDDIR := build
 
 SRC_C = \
-	lib/buffer.c \
 	lib/crc32b.c \
 	lib/fuse_opt.c \
 	lib/fuse_session.c \
@@ -74,10 +90,17 @@ OBJS += $(SRC_CXX:lib/%.cpp=$(BUILDDIR)/.objs/%.cpp.o)
 DEPS := $(SRC_C:lib/%.c=$(BUILDDIR)/.objs/%.c.d)
 DEPS += $(SRC_CXX:lib/%.cpp=$(BUILDDIR)/.objs/%.cpp.d)
 
+ifdef STATIC
+STATIC_FLAGS := -static
+else
+STATIC_FLAGS :=
+endif
+
 CPPFLAGS ?=
 CFLAGS ?= \
 	$(OPT_FLAGS) \
 	$(LTO_FLAGS) \
+	$(STATIC_FLAGS) \
 	-Wall \
 	-pipe
 override CFLAGS += \
@@ -87,6 +110,7 @@ override CFLAGS += \
 CXXFLAGS ?= \
 	$(OPT_FLAGS) \
 	$(LTO_FLAGS) \
+	$(STATIC_FLAGS) \
 	-Wall \
 	-pipe
 override CXXFLAGS += \
@@ -124,6 +148,7 @@ $(BUILDDIR)/mergerfs-fusermount: util/fusermount.c lib/mount_util.c
 mergerfs-fusermount: $(BUILDDIR)/mergerfs-fusermount
 
 $(BUILDDIR)/mount.mergerfs: $(BUILDDIR)/libfuse.a util/mount.mergerfs.c
+	echo STATIC=$(STATIC) $(STATIC_FLAGS)
 	$(CC) $(CFLAGS) $(FUSE_FLAGS) -o $(BUILDDIR)/mount.mergerfs util/mount.mergerfs.c $(BUILDDIR)/libfuse.a $(LDFLAGS)
 
 mount.mergerfs: $(BUILDDIR)/mount.mergerfs

libfuse/include/base_types.h

@@ -0,0 +1,24 @@
+#pragma once
+
+#include <stdint.h>
+
+typedef uint32_t u32;
+typedef int32_t  s32;
+typedef uint64_t u64;
+typedef int64_t  s64;
+
+typedef const uint32_t cu32;
+typedef const int32_t  cs32;
+typedef const uint64_t cu64;
+typedef const int64_t  cs64;
+
+typedef float       f32;
+typedef double      f64;
+typedef long double f80;
+typedef char assertion_f32_is_32bit[sizeof(f32) == 4 ? 1 : -1];
+typedef char assertion_f64_is_64bit[sizeof(f64) == 8 ? 1 : -1];
+typedef char assertion_f80_is_at_least_64bit[sizeof(f64) >= 8 ? 1 : -1];
+
+typedef const float       cf32;
+typedef const double      cf64;
+typedef const long double cf80;

libfuse/include/fuse_cfg.hpp

@@ -1,6 +1,6 @@
 #pragma once
 
-#include "int_types.h"
+#include "base_types.h"
 
 #include <climits>
 #include <string>

libfuse/include/fuse_common.h

@@ -330,70 +330,6 @@ struct fuse_buf {
   off_t pos;
 };
 
-/**
- * Data buffer vector
- *
- * An array of data buffers, each containing a memory pointer or a
- * file descriptor.
- *
- * Allocate dynamically to add more than one buffer.
- */
-struct fuse_bufvec {
-  /**
-   * Number of buffers in the array
-   */
-  size_t count;
-
-  /**
-   * Index of current buffer within the array
-   */
-  size_t idx;
-
-  /**
-   * Current offset within the current buffer
-   */
-  size_t off;
-
-  /**
-   * Array of buffers
-   */
-  struct fuse_buf buf[1];
-};
-
-/* Initialize bufvec with a single buffer of given size */
-#define FUSE_BUFVEC_INIT(size__)                        \
-  ((struct fuse_bufvec) {                               \
-    /* .count= */ 1,                                    \
-      /* .idx =  */ 0,                                  \
-      /* .off =  */ 0,                                  \
-      /* .buf =  */ { /* [0] = */ {			\
-        /* .size =  */ (size__),                        \
-          /* .flags = */ (enum fuse_buf_flags) 0,	\
-          /* .mem =   */ NULL,                          \
-          /* .fd =    */ -1,                            \
-          /* .pos =   */ 0,                             \
-          } }						\
-  } )
-
-/**
- * Get total size of data in a fuse buffer vector
- *
- * @param bufv buffer vector
- * @return size of data
- */
-size_t fuse_buf_size(const struct fuse_bufvec *bufv);
-
-/**
- * Copy data from one buffer vector to another
- *
- * @param dst destination buffer vector
- * @param src source buffer vector
- * @param flags flags controlling the copy
- * @return actual number of bytes copied or -errno on error
- */
-ssize_t fuse_buf_copy(struct fuse_bufvec *dst, struct fuse_bufvec *src,
-                      enum fuse_buf_copy_flags flags);
-
 /* ----------------------------------------------------------- *
  * Signal handling					       *
  * ----------------------------------------------------------- */

libfuse/include/fuse_lowlevel.h

@@ -472,30 +472,6 @@ int fuse_lowlevel_notify_delete(struct fuse_chan *ch,
                                 uint64_t parent, uint64_t child,
                                 const char *name, size_t namelen);
 
-/**
- * Store data to the kernel buffers
- *
- * Synchronously store data in the kernel buffers belonging to the
- * given inode.  The stored data is marked up-to-date (no read will be
- * performed against it, unless it's invalidated or evicted from the
- * cache).
- *
- * If the stored data overflows the current file size, then the size
- * is extended, similarly to a write(2) on the filesystem.
- *
- * If this function returns an error, then the store wasn't fully
- * completed, but it may have been partially completed.
- *
- * @param ch the channel through which to send the invalidation
- * @param ino the inode number
- * @param offset the starting offset into the file to store to
- * @param bufv buffer vector
- * @param flags flags controlling the copy
- * @return zero for success, -errno for failure
- */
-int fuse_lowlevel_notify_store(struct fuse_chan *ch, uint64_t ino,
-                               off_t offset, struct fuse_bufvec *bufv,
-                               enum fuse_buf_copy_flags flags);
 /**
  * Retrieve data from the kernel buffers
  *

libfuse/include/fuse_msgbuf.hpp

@@ -18,7 +18,7 @@
 
 #pragma once
 
-#include "int_types.h"
+#include "base_types.h"
 #include "fuse_msgbuf_t.h"
 
 u32      msgbuf_get_pagesize();

libfuse/include/int_types.h

@@ -1,13 +0,0 @@
-#pragma once
-
-#include <stdint.h>
-
-typedef uint64_t u32;
-typedef int64_t  s32;
-typedef uint64_t u64;
-typedef int64_t  s64;
-
-typedef const uint64_t cu32;
-typedef const int64_t  cs32;
-typedef const uint64_t cu64;
-typedef const int64_t  cs64;

libfuse/lib/buffer.c

@@ -1,316 +0,0 @@
-/*
-  FUSE: Filesystem in Userspace
-  Copyright (C) 2010  Miklos Szeredi <miklos@szeredi.hu>
-
-  This program can be distributed under the terms of the GNU LGPLv2.
-  See the file COPYING.LIB
-*/
-
-#define _GNU_SOURCE
-
-#include "fuse_i.h"
-#include "fuse_lowlevel.h"
-#include <string.h>
-#include <unistd.h>
-#include <errno.h>
-#include <assert.h>
-
-size_t fuse_buf_size(const struct fuse_bufvec *bufv)
-{
-  size_t i;
-  size_t size = 0;
-
-  for (i = 0; i < bufv->count; i++) {
-    if (bufv->buf[i].size == SIZE_MAX)
-      size = SIZE_MAX;
-    else
-      size += bufv->buf[i].size;
-  }
-
-  return size;
-}
-
-static size_t min_size(size_t s1, size_t s2)
-{
-  return s1 < s2 ? s1 : s2;
-}
-
-static ssize_t fuse_buf_write(const struct fuse_buf *dst, size_t dst_off,
-			      const struct fuse_buf *src, size_t src_off,
-			      size_t len)
-{
-  ssize_t res = 0;
-  size_t copied = 0;
-
-  while (len) {
-    if (dst->flags & FUSE_BUF_FD_SEEK) {
-      res = pwrite(dst->fd, src->mem + src_off, len,
-                   dst->pos + dst_off);
-    } else {
-      res = write(dst->fd, src->mem + src_off, len);
-    }
-    if (res == -1) {
-      if (!copied)
-        return -errno;
-      break;
-    }
-    if (res == 0)
-      break;
-
-    copied += res;
-    if (!(dst->flags & FUSE_BUF_FD_RETRY))
-      break;
-
-    src_off += res;
-    dst_off += res;
-    len -= res;
-  }
-
-  return copied;
-}
-
-static ssize_t fuse_buf_read(const struct fuse_buf *dst, size_t dst_off,
-			     const struct fuse_buf *src, size_t src_off,
-			     size_t len)
-{
-  ssize_t res = 0;
-  size_t copied = 0;
-
-  while (len) {
-    if (src->flags & FUSE_BUF_FD_SEEK) {
-      res = pread(src->fd, dst->mem + dst_off, len,
-                  src->pos + src_off);
-    } else {
-      res = read(src->fd, dst->mem + dst_off, len);
-    }
-    if (res == -1) {
-      if (!copied)
-        return -errno;
-      break;
-    }
-    if (res == 0)
-      break;
-
-    copied += res;
-    if (!(src->flags & FUSE_BUF_FD_RETRY))
-      break;
-
-    dst_off += res;
-    src_off += res;
-    len -= res;
-  }
-
-  return copied;
-}
-
-static ssize_t fuse_buf_fd_to_fd(const struct fuse_buf *dst, size_t dst_off,
-				 const struct fuse_buf *src, size_t src_off,
-				 size_t len)
-{
-  char buf[4096];
-  struct fuse_buf tmp = {
-    .size = sizeof(buf),
-    .flags = 0,
-  };
-  ssize_t res;
-  size_t copied = 0;
-
-  tmp.mem = buf;
-
-  while (len) {
-    size_t this_len = min_size(tmp.size, len);
-    size_t read_len;
-
-    res = fuse_buf_read(&tmp, 0, src, src_off, this_len);
-    if (res < 0) {
-      if (!copied)
-        return res;
-      break;
-    }
-    if (res == 0)
-      break;
-
-    read_len = res;
-    res = fuse_buf_write(dst, dst_off, &tmp, 0, read_len);
-    if (res < 0) {
-      if (!copied)
-        return res;
-      break;
-    }
-    if (res == 0)
-      break;
-
-    copied += res;
-
-    if (res < this_len)
-      break;
-
-    dst_off += res;
-    src_off += res;
-    len -= res;
-  }
-
-  return copied;
-}
-
-#ifdef HAVE_SPLICE
-static ssize_t fuse_buf_splice(const struct fuse_buf *dst, size_t dst_off,
-			       const struct fuse_buf *src, size_t src_off,
-			       size_t len, enum fuse_buf_copy_flags flags)
-{
-  int splice_flags = 0;
-  off_t *srcpos = NULL;
-  off_t *dstpos = NULL;
-  off_t srcpos_val;
-  off_t dstpos_val;
-  ssize_t res;
-  size_t copied = 0;
-
-  if (flags & FUSE_BUF_SPLICE_MOVE)
-    splice_flags |= SPLICE_F_MOVE;
-  if (flags & FUSE_BUF_SPLICE_NONBLOCK)
-    splice_flags |= SPLICE_F_NONBLOCK;
-
-  if (src->flags & FUSE_BUF_FD_SEEK) {
-    srcpos_val = src->pos + src_off;
-    srcpos = &srcpos_val;
-  }
-  if (dst->flags & FUSE_BUF_FD_SEEK) {
-    dstpos_val = dst->pos + dst_off;
-    dstpos = &dstpos_val;
-  }
-
-  while (len) {
-    res = splice(src->fd, srcpos, dst->fd, dstpos, len, splice_flags);
-    if (res == -1) {
-      if (copied)
-        break;
-
-      if (errno != EINVAL || (flags & FUSE_BUF_FORCE_SPLICE))
-        return -errno;
-
-      /* Maybe splice is not supported for this combination */
-      return fuse_buf_fd_to_fd(dst, dst_off, src, src_off,
-                               len);
-    }
-    if (res == 0)
-      break;
-
-    copied += res;
-    if (!(src->flags & FUSE_BUF_FD_RETRY) &&
-        !(dst->flags & FUSE_BUF_FD_RETRY)) {
-      break;
-    }
-
-    len -= res;
-  }
-
-  return copied;
-}
-#else
-static ssize_t fuse_buf_splice(const struct fuse_buf *dst, size_t dst_off,
-			       const struct fuse_buf *src, size_t src_off,
-			       size_t len, enum fuse_buf_copy_flags flags)
-{
-  (void) flags;
-
-  return fuse_buf_fd_to_fd(dst, dst_off, src, src_off, len);
-}
-#endif
-
-
-static ssize_t fuse_buf_copy_one(const struct fuse_buf *dst, size_t dst_off,
-				 const struct fuse_buf *src, size_t src_off,
-				 size_t len, enum fuse_buf_copy_flags flags)
-{
-  int src_is_fd = src->flags & FUSE_BUF_IS_FD;
-  int dst_is_fd = dst->flags & FUSE_BUF_IS_FD;
-
-  if (!src_is_fd && !dst_is_fd) {
-    char *dstmem = dst->mem + dst_off;
-    char *srcmem = src->mem + src_off;
-
-    if (dstmem != srcmem) {
-      if (dstmem + len <= srcmem || srcmem + len <= dstmem)
-        memcpy(dstmem, srcmem, len);
-      else
-        memmove(dstmem, srcmem, len);
-    }
-
-    return len;
-  } else if (!src_is_fd) {
-    return fuse_buf_write(dst, dst_off, src, src_off, len);
-  } else if (!dst_is_fd) {
-    return fuse_buf_read(dst, dst_off, src, src_off, len);
-  } else if (flags & FUSE_BUF_NO_SPLICE) {
-    return fuse_buf_fd_to_fd(dst, dst_off, src, src_off, len);
-  } else {
-    return fuse_buf_splice(dst, dst_off, src, src_off, len, flags);
-  }
-}
-
-static const struct fuse_buf *fuse_bufvec_current(struct fuse_bufvec *bufv)
-{
-  if (bufv->idx < bufv->count)
-    return &bufv->buf[bufv->idx];
-  else
-    return NULL;
-}
-
-static int fuse_bufvec_advance(struct fuse_bufvec *bufv, size_t len)
-{
-  const struct fuse_buf *buf = fuse_bufvec_current(bufv);
-
-  bufv->off += len;
-  assert(bufv->off <= buf->size);
-  if (bufv->off == buf->size) {
-    assert(bufv->idx < bufv->count);
-    bufv->idx++;
-    if (bufv->idx == bufv->count)
-      return 0;
-    bufv->off = 0;
-  }
-  return 1;
-}
-
-ssize_t fuse_buf_copy(struct fuse_bufvec *dstv, struct fuse_bufvec *srcv,
-		      enum fuse_buf_copy_flags flags)
-{
-  size_t copied = 0;
-
-  if (dstv == srcv)
-    return fuse_buf_size(dstv);
-
-  for (;;) {
-    const struct fuse_buf *src = fuse_bufvec_current(srcv);
-    const struct fuse_buf *dst = fuse_bufvec_current(dstv);
-    size_t src_len;
-    size_t dst_len;
-    size_t len;
-    ssize_t res;
-
-    if (src == NULL || dst == NULL)
-      break;
-
-    src_len = src->size - srcv->off;
-    dst_len = dst->size - dstv->off;
-    len = min_size(src_len, dst_len);
-
-    res = fuse_buf_copy_one(dst, dstv->off, src, srcv->off, len, flags);
-    if (res < 0) {
-      if (!copied)
-        return res;
-      break;
-    }
-    copied += res;
-
-    if (!fuse_bufvec_advance(srcv, res) ||
-        !fuse_bufvec_advance(dstv, res))
-      break;
-
-    if (res < len)
-      break;
-  }
-
-  return copied;
-}

libfuse/lib/crc32b.c

@@ -78,8 +78,8 @@ crc32b_continue(const void     *buf_,
                 const crc32b_t  len_,
                 const crc32b_t  crc_)
 {
-  int i;
   char *buf;
+  crc32b_t i;
   crc32b_t crc;
 
   crc = crc_;

libfuse/lib/debug.cpp

@@ -275,7 +275,9 @@ static
 void
 debug_open_flags(const uint32_t flags_)
 {
-  fmt::print("{}, ",open_accmode_to_str(flags_));
+  fmt::print(g_OUTPUT,
+             "{}, ",
+             open_accmode_to_str(flags_));
   for(size_t i = 0; i < (sizeof(flags_) * 8); i++)
     {
       const char *str;
@@ -287,7 +289,7 @@ debug_open_flags(const uint32_t flags_)
       if(str == NULL)
         continue;
 
-      fmt::print("{}, ",str);
+      fmt::print(g_OUTPUT,"{}, ",str);
     }
 }
 
@@ -315,7 +317,7 @@ fuse_fopen_flag_to_str(const uint32_t offset_)
 void
 debug_fuse_open_out(const struct fuse_open_out *arg_)
 {
-  fmt::print(stderr,
+  fmt::print(g_OUTPUT,
              "fuse_open_out:"
              " fh=0x{:#08x};"
              " open_flags=0x{:#04x} (",
@@ -332,9 +334,9 @@ debug_fuse_open_out(const struct fuse_open_out *arg_)
       if(str == NULL)
         continue;
 
-      fmt::print(stderr,"{},",str);
+      fmt::print(g_OUTPUT,"{},",str);
     }
-  fmt::print(stderr,");\n");
+  fmt::print(g_OUTPUT,");\n");
 }
 
 static
@@ -445,7 +447,7 @@ debug_fuse_mkdir_in(const void *arg_)
              "fuse_mkdir_in:"
              " mode={:o};"
              " umask={:o};"
-             " name=%s;"
+             " name={};"
              "\n"
              ,
              arg->mode,
@@ -461,7 +463,7 @@ debug_fuse_unlink(const void *arg_)
 
   fmt::print(g_OUTPUT,
              "fuse_unlink:"
-             " name=%s;"
+             " name={};"
              "\n"
              ,
              name);
@@ -475,7 +477,7 @@ debug_fuse_rmdir(const void *arg_)
 
   fmt::print(g_OUTPUT,
              "fuse_mkdir:"
-             " name=%s;"
+             " name={};"
              "\n"
              ,
              name);
@@ -493,8 +495,8 @@ debug_fuse_symlink(const void *arg_)
 
   fmt::print(g_OUTPUT,
              "fuse_mkdir:"
-             " linkname=%s;"
-             " name=%s;"
+             " linkname={};"
+             " name={};"
              "\n"
              ,
              linkname,
@@ -514,9 +516,9 @@ debug_fuse_rename_in(const void *arg_)
 
   fmt::print(g_OUTPUT,
              "fuse_rename_in:"
-             " oldname=%s;"
+             " oldname={};"
              " newdir={};"
-             " newname=%s;"
+             " newname={};"
              "\n"
              ,
              oldname,
@@ -536,7 +538,7 @@ debug_fuse_link_in(const void *arg_)
   fmt::print(g_OUTPUT,
              "fuse_link_in:"
              " oldnodeid={};"
-             " name=%s;"
+             " name={};"
              "\n"
              ,
              arg->oldnodeid,
@@ -556,7 +558,7 @@ debug_fuse_create_in(const void *arg_)
              "fuse_create_in:"
              " mode={:o};"
              " umask={:o};"
-             " name=%s;"
+             " name={};"
              " flags=0x%X (",
              arg->mode,
              arg->umask,
@@ -574,7 +576,7 @@ debug_fuse_open_in(const void *arg_)
 
   fmt::print(g_OUTPUT,
              "fuse_open_in:"
-             " flags=0x%08X (",
+             " flags=0x{:08X} (",
              arg->flags);
   debug_open_flags(arg->flags);
   fmt::print(g_OUTPUT,");\n");
@@ -639,7 +641,7 @@ debug_fuse_write_in(const void *arg_)
       if(str == NULL)
         continue;
 
-      fmt::print(g_OUTPUT,"%s,",str);
+      fmt::print(g_OUTPUT,"{},",str);
     }
   fmt::print(g_OUTPUT,");\n");
 }
@@ -712,8 +714,8 @@ debug_fuse_setxattr_in(const void *arg_)
              "fuse_setxattr_in:"
              " size={};"
              " flags=0x%X;"
-             " name=%s;"
-             " value=%s;"
+             " name={};"
+             " value={};"
              "\n"
              ,
              arg->size,
@@ -734,7 +736,7 @@ debug_fuse_getxattr_in(const void *arg_)
   fmt::print(g_OUTPUT,
              "fuse_getxattr_in:"
              " size={};"
-             " name=%s;"
+             " name={};"
              "\n"
              ,
              arg->size,
@@ -763,7 +765,7 @@ debug_fuse_removexattr(const void *arg_)
 
   fmt::print(g_OUTPUT,
              "fuse_removexattr:"
-             " name=%s;"
+             " name={};"
              "\n"
              ,
              name);
@@ -816,7 +818,7 @@ debug_fuse_init_in(const struct fuse_init_in *arg_)
       if(str == NULL)
         continue;
 
-      fmt::print(g_OUTPUT,"%s, ",str);
+      fmt::print(g_OUTPUT,"{}, ",str);
     }
   fmt::print(g_OUTPUT,")\n");
 }
@@ -932,7 +934,7 @@ debug_fuse_init_out(const uint64_t              unique_,
       if(str == NULL)
         continue;
 
-      fmt::print(g_OUTPUT,"%s, ",str);
+      fmt::print(g_OUTPUT,"{}, ",str);
     }
 
   fmt::print(g_OUTPUT,
@@ -1100,13 +1102,14 @@ opcode_name(enum fuse_opcode op_)
 {
   static const char *names[] =
     {
-      "INVALID",
+      "INVALID0",
       "LOOKUP",
       "FORGET",
       "GETATTR",
       "SETATTR",
       "READLINK",
       "SYMLINK",
+      "INVALID1",
       "MKNOD",
       "MKDIR",
       "UNLINK",
@@ -1118,6 +1121,7 @@ opcode_name(enum fuse_opcode op_)
       "WRITE",
       "STATFS",
       "RELEASE",
+      "INVALID3",
       "FSYNC",
       "SETXATTR",
       "GETXATTR",
@@ -1147,7 +1151,10 @@ opcode_name(enum fuse_opcode op_)
       "LSEEK",
       "COPY_FILE_RANGE",
       "SETUPMAPPING",
-      "REMOVEMAPPING"
+      "REMOVEMAPPING",
+      "SYNCFS",
+      "TMPFILE",
+      "STATX"
     };
 
   if(op_ >= (sizeof(names) / sizeof(names[0])))
@@ -1161,9 +1168,9 @@ debug_fuse_in_header(const struct fuse_in_header *hdr_)
 {
   const void *arg = &hdr_[1];
 
-  fmt::print(stderr,
-             "unique=0x%016" PRIx64 ";"
-             " opcode=%s ({});"
+  fmt::print(g_OUTPUT,
+             "unique=0x{:016x};"
+             " opcode={} ({});"
              " nodeid={};"
              " uid={};"
              " gid={};"
@@ -1265,8 +1272,14 @@ debug_fuse_in_header(const struct fuse_in_header *hdr_)
     case FUSE_INTERRUPT:
       debug_fuse_interrupt_in(arg);
       break;
+    case FUSE_SYNCFS:
+      break;
+    case FUSE_TMPFILE:
+      break;
+    case FUSE_STATX:
+      break;
     default:
-      fmt::print(g_OUTPUT,"FIXME\n");
+      fmt::print(g_OUTPUT,"FIXME: {}\n",hdr_->opcode);
       break;
     }
 }
@@ -1275,10 +1288,10 @@ void
 debug_fuse_out_header(const struct fuse_out_header *hdr_)
 {
   fmt::print(g_OUTPUT,
-             "unique=0x%016" PRIx64 ";"
+             "unique=0x{:016x};"
              " opcode=RESPONSE;"
-             " error=%d (%s);"
-             " len={};"
+             " error={} ({});"
+             " len={};\n"
              ,
              hdr_->unique,
              hdr_->error,
@@ -1312,7 +1325,7 @@ debug_fuse_readlink(const uint64_t  unique_,
              " opcode=RESPONSE;"
              " error=0 (Success);"
              " len={}; || "
-             "readlink: linkname=%s"
+             "readlink: linkname={}"
              "\n"
              ,
              unique_,

libfuse/lib/debug.hpp

@@ -51,6 +51,7 @@ void debug_fuse_lk_out(const uint64_t            unique,
 void debug_fuse_bmap_out(const uint64_t              unique,
                          const struct fuse_bmap_out *arg);
 void debug_fuse_in_header(const struct fuse_in_header *hdr);
+void debug_fuse_out_header(const struct fuse_out_header *hdr);
 
 std::string fuse_debug_init_flag_name(const uint64_t);
 

libfuse/lib/fuse.cpp

@@ -152,7 +152,7 @@ struct fuse_dh
   fuse_dirents_t  d;
 };
 
-static struct fuse f = {0};
+static struct fuse f = {};
 
 /*
   Why was the nodeid:generation logic simplified?
@@ -177,48 +177,6 @@ fuse_hdr_arg(const struct fuse_in_header *hdr_)
   return (void*)&hdr_[1];
 }
 
-static
-void
-list_add(struct list_head *new_,
-         struct list_head *prev_,
-         struct list_head *next_)
-{
-  next_->prev = new_;
-  new_->next  = next_;
-  new_->prev  = prev_;
-  prev_->next = new_;
-}
-
-static
-inline
-void
-list_add_head(struct list_head *new_,
-              struct list_head *head_)
-{
-  list_add(new_,head_,head_->next);
-}
-
-static
-inline
-void
-list_add_tail(struct list_head *new_,
-              struct list_head *head_)
-{
-  list_add(new_,head_->prev,head_);
-}
-
-static
-inline
-void
-list_del(struct list_head *entry)
-{
-  struct list_head *prev = entry->prev;
-  struct list_head *next = entry->next;
-
-  next->prev = prev;
-  prev->next = next;
-}
-
 static
 size_t
 id_hash(uint64_t ino)
@@ -1020,7 +978,7 @@ get_path_common(uint64_t     nodeid,
   err = try_get_path(nodeid,name,path,wnode,true);
   if(err == -EAGAIN)
     {
-      struct lock_queue_element qe = {0};
+      struct lock_queue_element qe = {};
 
       qe.nodeid1 = nodeid;
       qe.name1   = name;
@@ -1079,7 +1037,7 @@ get_path2(uint64_t     nodeid1,
                       path1,path2,wnode1,wnode2);
   if(err == -EAGAIN)
     {
-      struct lock_queue_element qe = {0};
+      struct lock_queue_element qe = {};
 
       qe.nodeid1 = nodeid1;
       qe.name1   = name1;
@@ -1157,7 +1115,7 @@ forget_node(const uint64_t nodeid,
    */
   while(node->nlookup == nlookup && node->treelock)
     {
-      struct lock_queue_element qe = {0};
+      struct lock_queue_element qe = {};
 
       qe.nodeid1 = nodeid;
 
@@ -1389,7 +1347,7 @@ fuse_lib_lookup(fuse_req_t            *req_,
   char *fusepath;
   const char *name;
   node_t *dot = NULL;
-  struct fuse_entry_param e = {0};
+  struct fuse_entry_param e = {};
 
   name   = (const char*)fuse_hdr_arg(hdr_);
   nodeid = hdr_->nodeid;
@@ -1622,7 +1580,7 @@ fuse_lib_setattr(fuse_req_t            *req_,
                  struct fuse_in_header *hdr_)
 {
   uint64_t fh;
-  struct stat stbuf = {0};
+  struct stat stbuf = {};
   char *fusepath;
   int err;
   fuse_timeouts_t timeout;
@@ -1678,12 +1636,12 @@ fuse_lib_setattr(fuse_req_t            *req_,
           if(arg->valid & FATTR_ATIME_NOW)
             tv[0].tv_nsec = UTIME_NOW;
           else if(arg->valid & FATTR_ATIME)
-            tv[0] = (struct timespec){ static_cast<time_t>(arg->atime), arg->atimensec };
+            tv[0] = (struct timespec){ static_cast<time_t>(arg->atime), static_cast<long>(arg->atimensec) };
 
           if(arg->valid & FATTR_MTIME_NOW)
             tv[1].tv_nsec = UTIME_NOW;
           else if(arg->valid & FATTR_MTIME)
-            tv[1] = (struct timespec){ static_cast<time_t>(arg->mtime), arg->mtimensec };
+            tv[1] = (struct timespec){ static_cast<time_t>(arg->mtime), static_cast<long>(arg->mtimensec) };
 
           err = ((fusepath != NULL) ?
                  f.ops.utimens(&req_->ctx,&fusepath[1],tv) :
@@ -1927,7 +1885,7 @@ fuse_lib_symlink(fuse_req_t            *req_,
   char *fusepath;
   const char *name;
   const char *linkname;
-  struct fuse_entry_param e = {0};
+  struct fuse_entry_param e = {};
 
   name     = (const char*)fuse_hdr_arg(hdr_);
   linkname = (name + strlen(name) + 1);
@@ -2017,7 +1975,7 @@ fuse_lib_link(fuse_req_t            *req_,
   char *newpath;
   const char *newname;
   struct fuse_link_in *arg;
-  struct fuse_entry_param e = {0};
+  struct fuse_entry_param e = {};
 
   arg     = (fuse_link_in*)fuse_hdr_arg(hdr_);
   newname = (const char*)PARAM(arg);
@@ -2074,7 +2032,7 @@ fuse_lib_create(fuse_req_t            *req_,
   char *fusepath;
   const char *name;
   uint64_t new_nodeid;
-  fuse_file_info_t ffi = {0};
+  fuse_file_info_t ffi = {};
   struct fuse_entry_param e;
   struct fuse_create_in *arg;
 
@@ -2188,7 +2146,7 @@ fuse_lib_open(fuse_req_t            *req_,
 {
   int err;
   char *fusepath;
-  fuse_file_info_t ffi = {0};
+  fuse_file_info_t ffi = {};
   struct fuse_open_in *arg;
 
   arg     = (fuse_open_in*)fuse_hdr_arg(hdr_);
@@ -2231,7 +2189,7 @@ fuse_lib_read(fuse_req_t            *req_,
               struct fuse_in_header *hdr_)
 {
   int res;
-  fuse_file_info_t ffi = {0};
+  fuse_file_info_t ffi = {};
   struct fuse_read_in *arg;
   fuse_msgbuf_t *msgbuf;
 
@@ -2266,7 +2224,7 @@ fuse_lib_write(fuse_req_t            *req_,
 {
   int res;
   char *data;
-  fuse_file_info_t ffi = {0};
+  fuse_file_info_t ffi = {};
   struct fuse_write_in *arg;
 
   arg     = (fuse_write_in*)fuse_hdr_arg(hdr_);
@@ -2335,8 +2293,8 @@ fuse_lib_opendir(fuse_req_t            *req_,
   int err;
   char *fusepath;
   struct fuse_dh *dh;
-  fuse_file_info_t llffi = {0};
-  fuse_file_info_t ffi = {0};
+  fuse_file_info_t llffi = {};
+  fuse_file_info_t ffi = {};
   struct fuse_open_in *arg;
 
   arg = (fuse_open_in*)fuse_hdr_arg(hdr_);
@@ -2422,8 +2380,8 @@ fuse_lib_readdir(fuse_req_t            *req_,
   size_t size;
   fuse_dirents_t *d;
   struct fuse_dh *dh;
-  fuse_file_info_t ffi = {0};
-  fuse_file_info_t llffi = {0};
+  fuse_file_info_t ffi = {};
+  fuse_file_info_t llffi = {};
   struct fuse_read_in *arg;
 
   arg      = (fuse_read_in*)fuse_hdr_arg(hdr_);
@@ -2466,8 +2424,8 @@ fuse_lib_readdir_plus(fuse_req_t            *req_,
   size_t size;
   fuse_dirents_t *d;
   struct fuse_dh *dh;
-  fuse_file_info_t ffi = {0};
-  fuse_file_info_t llffi = {0};
+  fuse_file_info_t ffi = {};
+  fuse_file_info_t llffi = {};
   struct fuse_read_in *arg;
 
   arg      = (fuse_read_in*)fuse_hdr_arg(hdr_);
@@ -2508,7 +2466,7 @@ fuse_lib_releasedir(fuse_req_t            *req_,
 {
   struct fuse_dh *dh;
   fuse_file_info_t ffi;
-  fuse_file_info_t llffi = {0};
+  fuse_file_info_t llffi = {};
   struct fuse_release_in *arg;
 
   arg = (fuse_release_in*)fuse_hdr_arg(hdr_);
@@ -2537,7 +2495,7 @@ fuse_lib_fsyncdir(fuse_req_t            *req_,
   int err;
   int is_datasync;
   fuse_file_info_t ffi;
-  fuse_file_info_t llffi = {0};
+  fuse_file_info_t llffi = {};
   struct fuse_fsync_in *arg;
 
   arg         = (fuse_fsync_in*)fuse_hdr_arg(hdr_);
@@ -2560,7 +2518,7 @@ fuse_lib_statfs(fuse_req_t            *req_,
 {
   int err = 0;
   char *fusepath;
-  struct statvfs buf = {0};
+  struct statvfs buf = {};
 
   fusepath = NULL;
   if(hdr_->nodeid)
@@ -2767,8 +2725,8 @@ fuse_lib_copy_file_range(fuse_req_t                  *req_,
                          const struct fuse_in_header *hdr_)
 {
   ssize_t rv;
-  fuse_file_info_t ffi_in = {0};
-  fuse_file_info_t ffi_out = {0};
+  fuse_file_info_t ffi_in = {};
+  fuse_file_info_t ffi_out = {};
   const struct fuse_copy_file_range_in *arg;
 
   arg = (fuse_copy_file_range_in*)fuse_hdr_arg(hdr_);
@@ -2825,7 +2783,7 @@ fuse_lib_tmpfile(fuse_req_t                  *req_,
   int err;
   char *fusepath;
   const char *name;
-  fuse_file_info_t ffi = {0};
+  fuse_file_info_t ffi = {};
   struct fuse_entry_param e;
   struct fuse_create_in *arg;
 
@@ -3072,7 +3030,7 @@ fuse_lib_release(fuse_req_t            *req_,
                  struct fuse_in_header *hdr_)
 {
   int err = 0;
-  fuse_file_info_t ffi = {0};
+  fuse_file_info_t ffi = {};
   struct fuse_release_in *arg;
 
   arg = (fuse_release_in*)fuse_hdr_arg(hdr_);
@@ -3109,7 +3067,7 @@ fuse_lib_flush(fuse_req_t             *req_,
                struct fuse_in_header *hdr_)
 {
   int err;
-  fuse_file_info_t ffi = {0};
+  fuse_file_info_t ffi = {};
   struct fuse_flush_in *arg;
 
   arg = (fuse_flush_in*)fuse_hdr_arg(hdr_);
@@ -3167,7 +3125,7 @@ fuse_lib_getlk(fuse_req_t                  *req_,
   lock_t lk;
   struct flock flk;
   lock_t *conflict;
-  fuse_file_info_t ffi = {0};
+  fuse_file_info_t ffi = {};
   const struct fuse_lk_in *arg;
 
   arg            = (fuse_lk_in*)fuse_hdr_arg(hdr_);
@@ -3270,7 +3228,7 @@ fuse_lib_ioctl(fuse_req_t                  *req_,
   int err;
   char *out_buf = NULL;
   fuse_file_info_t ffi;
-  fuse_file_info_t llffi = {0};
+  fuse_file_info_t llffi = {};
   const void *in_buf;
   uint32_t out_size;
   const struct fuse_ioctl_in *arg;
@@ -3339,7 +3297,7 @@ fuse_lib_poll(fuse_req_t                  *req_,
 {
   int err;
   unsigned revents = 0;
-  fuse_file_info_t ffi = {0};
+  fuse_file_info_t ffi = {};
   fuse_pollhandle_t *ph = NULL;
   const struct fuse_poll_in *arg;
 
@@ -3428,7 +3386,7 @@ fuse_prune_some_remembered_nodes(int *offset_)
   pruned = 0;
   checked = 0;
   now = current_time();
-  while(*offset_ < kv_size(f.remembered_nodes))
+  while(*offset_ < (int)kv_size(f.remembered_nodes))
     {
       time_t age;
       remembered_node_t *fn = &kv_A(f.remembered_nodes,*offset_);
@@ -3913,7 +3871,7 @@ fuse_passthrough_open(const int fd_)
 {
   int rv;
   int dev_fuse_fd;
-  struct fuse_backing_map bm = {0};
+  struct fuse_backing_map bm = {};
 
   dev_fuse_fd = fuse_chan_fd(f.se->ch);
   bm.fd       = fd_;

libfuse/lib/fuse_lowlevel.cpp

@@ -292,7 +292,7 @@ int
 fuse_reply_entry(fuse_req_t                    *req,
                  const struct fuse_entry_param *e)
 {
-  struct fuse_entry_out arg = {0};
+  struct fuse_entry_out arg = {};
   size_t size = req->f->conn.proto_minor < 9 ?
     FUSE_COMPAT_ENTRY_OUT_SIZE : sizeof(arg);
 
@@ -322,7 +322,7 @@ fuse_reply_create(fuse_req_t                    *req,
                   const struct fuse_entry_param *e,
                   const fuse_file_info_t        *f)
 {
-  struct fuse_create_out buf = {0};
+  struct fuse_create_out buf = {};
   size_t entrysize = req->f->conn.proto_minor < 9 ?
     FUSE_COMPAT_ENTRY_OUT_SIZE : sizeof(struct fuse_entry_out);
   struct fuse_entry_out *earg = (struct fuse_entry_out*)&buf.e;
@@ -339,7 +339,7 @@ fuse_reply_attr(fuse_req_t        *req,
                 const struct stat *attr,
                 const uint64_t     timeout)
 {
-  struct fuse_attr_out arg = {0};
+  struct fuse_attr_out arg = {};
   size_t size = req->f->conn.proto_minor < 9 ?
     FUSE_COMPAT_ATTR_OUT_SIZE : sizeof(arg);
 
@@ -377,7 +377,7 @@ int
 fuse_reply_open(fuse_req_t             *req,
                 const fuse_file_info_t *f)
 {
-  struct fuse_open_out arg = {0};
+  struct fuse_open_out arg = {};
 
   fill_open(&arg, f);
 
@@ -388,7 +388,7 @@ int
 fuse_reply_write(fuse_req_t *req,
                  size_t      count)
 {
-  struct fuse_write_out arg = {0};
+  struct fuse_write_out arg = {};
 
   arg.size = count;
 
@@ -403,55 +403,6 @@ fuse_reply_buf(fuse_req_t *req,
   return send_reply_ok(req, buf, size);
 }
 
-static
-int
-fuse_send_data_iov_fallback(struct fuse_ll     *f,
-                            struct fuse_chan   *ch,
-                            struct iovec       *iov,
-                            int                 iov_count,
-                            struct fuse_bufvec *buf,
-                            size_t              len)
-{
-  int res;
-  struct fuse_bufvec mem_buf = FUSE_BUFVEC_INIT(len);
-
-  /* Optimize common case */
-  if(buf->count == 1 && buf->idx == 0 && buf->off == 0 &&
-      !(buf->buf[0].flags & FUSE_BUF_IS_FD))
-    {
-      /* FIXME: also avoid memory copy if there are multiple buffers
-         but none of them contain an fd */
-
-      iov[iov_count].iov_base = buf->buf[0].mem;
-      iov[iov_count].iov_len = len;
-      iov_count++;
-
-      return fuse_send_msg(f, ch, iov, iov_count);
-    }
-
-  fuse_msgbuf_t *msgbuf;
-  msgbuf = msgbuf_alloc();
-  if(msgbuf == NULL)
-    return -ENOMEM;
-
-  mem_buf.buf[0].mem = msgbuf->mem;
-  res = fuse_buf_copy(&mem_buf, buf, (fuse_buf_copy_flags)0);
-  if(res < 0)
-    {
-      msgbuf_free(msgbuf);
-      return -res;
-    }
-  len = res;
-
-  iov[iov_count].iov_base = msgbuf->mem;
-  iov[iov_count].iov_len = len;
-  iov_count++;
-  res = fuse_send_msg(f, ch, iov, iov_count);
-  msgbuf_free(msgbuf);
-
-  return res;
-}
-
 struct fuse_ll_pipe
 {
   size_t size;
@@ -468,21 +419,6 @@ fuse_ll_pipe_free(struct fuse_ll_pipe *llp)
   free(llp);
 }
 
-static
-int
-fuse_send_data_iov(struct fuse_ll     *f,
-                   struct fuse_chan   *ch,
-                   struct iovec       *iov,
-                   int                 iov_count,
-                   struct fuse_bufvec *buf,
-                   unsigned int        flags)
-{
-  size_t len = fuse_buf_size(buf);
-  (void) flags;
-
-  return fuse_send_data_iov_fallback(f, ch, iov, iov_count, buf, len);
-}
-
 int
 fuse_reply_data(fuse_req_t   *req,
                 char         *buf_,
@@ -516,7 +452,7 @@ int
 fuse_reply_statfs(fuse_req_t           *req,
                   const struct statvfs *stbuf)
 {
-  struct fuse_statfs_out arg = {0};
+  struct fuse_statfs_out arg = {};
   size_t size = req->f->conn.proto_minor < 4 ?
     FUSE_COMPAT_STATFS_SIZE : sizeof(arg);
 
@@ -529,7 +465,7 @@ int
 fuse_reply_xattr(fuse_req_t *req,
                  size_t      count)
 {
-  struct fuse_getxattr_out arg = {0};
+  struct fuse_getxattr_out arg = {};
 
   arg.size = count;
 
@@ -540,7 +476,7 @@ int
 fuse_reply_lock(fuse_req_t         *req,
                 const struct flock *lock)
 {
-  struct fuse_lk_out arg = {0};
+  struct fuse_lk_out arg = {};
 
   arg.lk.type = lock->l_type;
   if(lock->l_type != F_UNLCK)
@@ -560,7 +496,7 @@ int
 fuse_reply_bmap(fuse_req_t *req,
                 uint64_t    idx)
 {
-  struct fuse_bmap_out arg = {0};
+  struct fuse_bmap_out arg = {};
 
   arg.block = idx;
 
@@ -595,7 +531,7 @@ fuse_reply_ioctl_retry(fuse_req_t         *req,
                        const struct iovec *out_iov,
                        size_t              out_count)
 {
-  struct fuse_ioctl_out arg = {0};
+  struct fuse_ioctl_out arg = {};
   struct fuse_ioctl_iovec *in_fiov = NULL;
   struct fuse_ioctl_iovec *out_fiov = NULL;
   struct iovec iov[4];
@@ -705,7 +641,7 @@ fuse_reply_ioctl_iov(fuse_req_t         *req,
                      int                 count)
 {
   struct iovec *padded_iov;
-  struct fuse_ioctl_out arg = {0};
+  struct fuse_ioctl_out arg = {};
   int res;
 
   padded_iov = (iovec*)malloc((count + 2) * sizeof(struct iovec));
@@ -728,7 +664,7 @@ int
 fuse_reply_poll(fuse_req_t *req,
                 unsigned    revents)
 {
-  struct fuse_poll_out arg = {0};
+  struct fuse_poll_out arg = {};
 
   arg.revents = revents;
 
@@ -1015,7 +951,7 @@ do_setlk_common(fuse_req_t *req,
                 int         sleep)
 {
   struct flock flock;
-  fuse_file_info_t fi = {0};
+  fuse_file_info_t fi = {};
   struct fuse_lk_in *arg = (struct fuse_lk_in*)inarg;
 
   fi.fh = arg->fh;
@@ -1118,7 +1054,7 @@ void
 do_init(fuse_req_t            *req,
         struct fuse_in_header *hdr_)
 {
-  struct fuse_init_out outarg = {0};
+  struct fuse_init_out outarg = {};
   struct fuse_init_in *arg = (struct fuse_init_in *)&hdr_[1];
   struct fuse_ll *f = req->f;
   size_t bufsize;
@@ -1604,50 +1540,6 @@ fuse_lowlevel_notify_delete(struct fuse_chan *ch,
   return send_notify_iov(f, ch, FUSE_NOTIFY_DELETE, iov, 3);
 }
 
-int
-fuse_lowlevel_notify_store(struct fuse_chan         *ch,
-                           uint64_t                  ino,
-                           off_t                     offset,
-                           struct fuse_bufvec       *bufv,
-                           enum fuse_buf_copy_flags  flags)
-{
-  struct fuse_out_header out;
-  struct fuse_notify_store_out outarg;
-  struct fuse_ll *f;
-  struct iovec iov[3];
-  size_t size = fuse_buf_size(bufv);
-  int res;
-
-  if(!ch)
-    return -EINVAL;
-
-  f = (struct fuse_ll*)fuse_session_data(fuse_chan_session(ch));
-  if(!f)
-    return -ENODEV;
-
-  if(f->conn.proto_minor < 15)
-    return -ENOSYS;
-
-  out.unique = 0;
-  out.error = FUSE_NOTIFY_STORE;
-
-  outarg.nodeid = ino;
-  outarg.offset = offset;
-  outarg.size = size;
-  outarg.padding = 0;
-
-  iov[0].iov_base = &out;
-  iov[0].iov_len = sizeof(out);
-  iov[1].iov_base = &outarg;
-  iov[1].iov_len = sizeof(outarg);
-
-  res = fuse_send_data_iov(f, ch, iov, 2, bufv, flags);
-  if(res > 0)
-    res = -res;
-
-  return res;
-}
-
 struct fuse_retrieve_req
 {
   struct fuse_notify_req nreq;
@@ -1825,8 +1717,8 @@ fuse_send_errno(struct fuse_ll   *f_,
                 const int         errno_,
                 const uint64_t    unique_id_)
 {
-  struct fuse_out_header out = {0};
-  struct iovec           iov = {0};
+  struct fuse_out_header out = {};
+  struct iovec           iov = {};
 
   out.unique   = unique_id_;
   out.error    = -errno_;
@@ -1845,14 +1737,14 @@ fuse_send_enomem(struct fuse_ll   *f_,
   fuse_send_errno(f_,ch_,ENOMEM,unique_id_);
 }
 
-static
-void
-fuse_send_einval(struct fuse_ll   *f_,
-                 struct fuse_chan *ch_,
-                 const uint64_t    unique_id_)
-{
-  fuse_send_errno(f_,ch_,EINVAL,unique_id_);
-}
+// static
+// void
+// fuse_send_einval(struct fuse_ll   *f_,
+//                  struct fuse_chan *ch_,
+//                  const uint64_t    unique_id_)
+// {
+//   fuse_send_errno(f_,ch_,EINVAL,unique_id_);
+// }
 
 static
 int
@@ -1885,9 +1777,6 @@ fuse_ll_buf_process_read(struct fuse_session *se_,
 
   in = (struct fuse_in_header*)msgbuf_->mem;
 
-  if((in->uid == FUSE_INVALID_UIDGID) || (in->gid == FUSE_INVALID_UIDGID))
-    return fuse_send_einval(se_->f,se_->ch,in->unique);
-
   req = fuse_ll_alloc_req(se_->f);
   if(req == NULL)
     return fuse_send_enomem(se_->f,se_->ch,in->unique);
@@ -1908,6 +1797,8 @@ fuse_ll_buf_process_read(struct fuse_session *se_,
   if(fuse_ll_funcs[in->opcode] == NULL)
     goto reply_err;
 
+  //  debug_fuse_in_header(in);
+
   fuse_ll_funcs[in->opcode](req, in);
 
   return;
@@ -1971,7 +1862,7 @@ fuse_ll_opt_proc(void             *data_,
                  int               key_,
                  struct fuse_args *outargs_)
 {
-  fmt::print(stderr, "* ERROR: unknown option '{}'\n", arg_);
+  fmt::print(stderr, "fuse: ERROR - unknown option - '{}'\n", arg_);
 
   return -1;
 }

libfuse/lib/helper.c

@@ -282,7 +282,7 @@ fuse_setup_common(int argc,
   if (res == -1)
     goto err_unmount;
 
-  res = fuse_set_signal_handlers(fuse_get_session(fuse));
+  res = fuse_set_signal_handlers(fuse_get_session());
   if (res == -1)
     goto err_unmount;
 

libfuse/lib/mount_bsd.c

@@ -184,13 +184,16 @@ void fuse_kern_unmount(const char *mountpoint, int fd)
 }
 
 /* Check if kernel is doing init in background */
-static int init_backgrounded(void)
+static
+int
+init_backgrounded(void)
 {
-  unsigned ibg, len;
+  unsigned ibg;
+  size_t len;
 
   len = sizeof(ibg);
 
-  if (sysctlbyname("vfs.fuse.init_backgrounded", &ibg, &len, NULL, 0))
+  if(sysctlbyname("vfs.fuse.init_backgrounded", &ibg, &len, NULL, 0))
     return 0;
 
   return ibg;
@@ -298,10 +301,12 @@ static int fuse_mount_core(const char *mountpoint, const char *opts)
   return fd;
 }
 
-int fuse_kern_mount(const char *mountpoint, struct fuse_args *args)
+int
+fuse_kern_mount(const char       *mountpoint,
+                struct fuse_args *args)
 {
-  struct mount_opts mo;
   int res = -1;
+  struct mount_opts mo;
 
   memset(&mo, 0, sizeof(mo));
   /* mount util should not try to spawn the daemon */
@@ -317,7 +322,6 @@ int fuse_kern_mount(const char *mountpoint, struct fuse_args *args)
     return 0;
 
   res = fuse_mount_core(mountpoint, mo.kernel_opts);
- out:
   free(mo.kernel_opts);
   return res;
 }

libfuse/lib/mount_generic.c

@@ -17,7 +17,7 @@
 #include <string.h>
 #include <fcntl.h>
 #include <errno.h>
-#include <sys/poll.h>
+#include <poll.h>
 #include <sys/socket.h>
 #include <sys/un.h>
 #include <sys/wait.h>

libfuse/util/mount.mergerfs.c

@@ -16,216 +16,221 @@ static char *progname;
 
 static char *xstrdup(const char *s)
 {
-	char *t = strdup(s);
-	if (!t) {
-		fprintf(stderr, "%s: failed to allocate memory\n", progname);
-		exit(1);
-	}
-	return t;
+  char *t = strdup(s);
+  if (!t) {
+    fprintf(stderr, "%s: failed to allocate memory\n", progname);
+    exit(1);
+  }
+  return t;
 }
 
 static void *xrealloc(void *oldptr, size_t size)
 {
-	void *ptr = realloc(oldptr, size);
-	if (!ptr) {
-		fprintf(stderr, "%s: failed to allocate memory\n", progname);
-		exit(1);
-	}
-	return ptr;
+  void *ptr = realloc(oldptr, size);
+  if (!ptr) {
+    fprintf(stderr, "%s: failed to allocate memory\n", progname);
+    exit(1);
+  }
+  return ptr;
 }
 
 static void add_arg(char **cmdp, const char *opt)
 {
-	size_t optlen = strlen(opt);
-	size_t cmdlen = *cmdp ? strlen(*cmdp) : 0;
-	char *cmd = xrealloc(*cmdp, cmdlen + optlen * 4 + 4);
-	char *s;
-	s = cmd + cmdlen;
-	if (*cmdp)
-		*s++ = ' ';
+  size_t optlen = strlen(opt);
+  size_t cmdlen = *cmdp ? strlen(*cmdp) : 0;
+  char *cmd = xrealloc(*cmdp, cmdlen + optlen * 4 + 4);
+  char *s;
+  s = cmd + cmdlen;
+  if (*cmdp)
+    *s++ = ' ';
 
-	*s++ = '\'';
-	for (; *opt; opt++) {
-		if (*opt == '\'') {
-			*s++ = '\'';
-			*s++ = '\\';
-			*s++ = '\'';
-			*s++ = '\'';
-		} else
-			*s++ = *opt;
-	}
-	*s++ = '\'';
-	*s = '\0';
-	*cmdp = cmd;
+  *s++ = '\'';
+  for (; *opt; opt++) {
+    if (*opt == '\'') {
+      *s++ = '\'';
+      *s++ = '\\';
+      *s++ = '\'';
+      *s++ = '\'';
+    } else
+      *s++ = *opt;
+  }
+  *s++ = '\'';
+  *s = '\0';
+  *cmdp = cmd;
 }
 
 static char *add_option(const char *opt, char *options)
 {
-	int oldlen = options ? strlen(options) : 0;
+  int oldlen = options ? strlen(options) : 0;
 
-	options = xrealloc(options, oldlen + 1 + strlen(opt) + 1);
-	if (!oldlen)
-		strcpy(options, opt);
-	else {
-		strcat(options, ",");
-		strcat(options, opt);
-	}
-	return options;
+  options = xrealloc(options, oldlen + 1 + strlen(opt) + 1);
+  if (!oldlen)
+    strcpy(options, opt);
+  else {
+    strcat(options, ",");
+    strcat(options, opt);
+  }
+  return options;
 }
 
 int main(int argc, char *argv[])
 {
-	char *type = NULL;
-	char *source;
-	const char *mountpoint;
-	char *basename;
-	char *options = NULL;
-	char *command = NULL;
-	char *setuid = NULL;
-	int i;
-	int dev = 1;
-	int suid = 1;
+  char *type = NULL;
+  char *source;
+  const char *mountpoint;
+  char *basename;
+  char *options = NULL;
+  char *command = NULL;
+  char *setuid = NULL;
+  int i;
+  int dev = 1;
+  int suid = 1;
 
-	progname = argv[0];
-	basename = strrchr(argv[0], '/');
-	if (basename)
-		basename++;
-	else
-		basename = argv[0];
+  progname = argv[0];
+  basename = strrchr(argv[0], '/');
+  if (basename)
+    basename++;
+  else
+    basename = argv[0];
 
-        type = "mergerfs";
-	if (strncmp(basename, "mount.fuse.", 11) == 0)
-		type = basename + 11;
-	if (strncmp(basename, "mount.fuseblk.", 14) == 0)
-		type = basename + 14;
+  type = "mergerfs";
+  if (strncmp(basename, "mount.fuse.", 11) == 0)
+    type = basename + 11;
+  if (strncmp(basename, "mount.fuseblk.", 14) == 0)
+    type = basename + 14;
 
-	if (type && !type[0])
-		type = NULL;
+  if (type && !type[0])
+    type = NULL;
 
-	if (argc < 3) {
-		fprintf(stderr,
-			"usage: %s %s destination [-t type] [-o opt[,opts...]]\n",
-			progname, type ? "source" : "type#[source]");
-		exit(1);
-	}
+  if (argc < 3) {
+    fprintf(stderr,
+            "usage: %s %s destination [-t type] [-o opt[,opts...]]\n",
+            progname, type ? "source" : "type#[source]");
+    exit(1);
+  }
 
-	source = argv[1];
-	if (!source[0])
-		source = NULL;
+  source = argv[1];
+  if (!source[0])
+    source = NULL;
 
-	mountpoint = argv[2];
+  mountpoint = argv[2];
 
-	for (i = 3; i < argc; i++) {
-		if (strcmp(argv[i], "-v") == 0) {
-			continue;
-		} else if (strcmp(argv[i], "-t") == 0) {
-			i++;
+  for (i = 3; i < argc; i++) {
+    if (strcmp(argv[i], "-v") == 0) {
+      continue;
+    } else if (strcmp(argv[i], "-t") == 0) {
+      i++;
 
-			if (i == argc) {
-				fprintf(stderr,
-					"%s: missing argument to option '-t'\n",
-					progname);
-				exit(1);
-			}
-			type = argv[i];
-			if (strncmp(type, "fuse.", 5) == 0)
-				type += 5;
-			else if (strncmp(type, "fuseblk.", 8) == 0)
-				type += 8;
+      if (i == argc) {
+        fprintf(stderr,
+                "%s: missing argument to option '-t'\n",
+                progname);
+        exit(1);
+      }
+      type = argv[i];
+      if (strncmp(type, "fuse.", 5) == 0)
+        type += 5;
+      else if (strncmp(type, "fuseblk.", 8) == 0)
+        type += 8;
 
-			if (!type[0]) {
-				fprintf(stderr,
-					"%s: empty type given as argument to option '-t'\n",
-					progname);
-				exit(1);
-			}
-		} else	if (strcmp(argv[i], "-o") == 0) {
-			char *opts;
-			char *opt;
-			i++;
-			if (i == argc)
-				break;
+      if (!type[0]) {
+        fprintf(stderr,
+                "%s: empty type given as argument to option '-t'\n",
+                progname);
+        exit(1);
+      }
+    } else	if (strcmp(argv[i], "-o") == 0) {
+      char *opts;
+      char *opt;
+      i++;
+      if (i == argc)
+        break;
 
-			opts = xstrdup(argv[i]);
-			opt = strtok(opts, ",");
-			while (opt) {
-				int j;
-				int ignore = 0;
-				const char *ignore_opts[] = { "",
-							      "user",
-							      "nouser",
-							      "users",
-							      "auto",
-							      "noauto",
-							      "_netdev",
-							      NULL};
-				if (strncmp(opt, "setuid=", 7) == 0) {
-					setuid = xstrdup(opt + 7);
-					ignore = 1;
-				}
-				for (j = 0; ignore_opts[j]; j++)
-					if (strcmp(opt, ignore_opts[j]) == 0)
-						ignore = 1;
+      opts = xstrdup(argv[i]);
+      opt = strtok(opts, ",");
+      while (opt)
+        {
+          int j;
+          int ignore = 0;
+          const char *ignore_opts[] =
+            {
+              "",
+              "nofail",
+              "user",
+              "nouser",
+              "users",
+              "auto",
+              "noauto",
+              "_netdev",
+              NULL
+            };
+        if (strncmp(opt, "setuid=", 7) == 0) {
+          setuid = xstrdup(opt + 7);
+          ignore = 1;
+        }
+        for (j = 0; ignore_opts[j]; j++)
+          if (strcmp(opt, ignore_opts[j]) == 0)
+            ignore = 1;
 
-				if (!ignore) {
-					if (strcmp(opt, "nodev") == 0)
-						dev = 0;
-					else if (strcmp(opt, "nosuid") == 0)
-						suid = 0;
+        if (!ignore) {
+          if (strcmp(opt, "nodev") == 0)
+            dev = 0;
+          else if (strcmp(opt, "nosuid") == 0)
+            suid = 0;
 
-					options = add_option(opt, options);
-				}
-				opt = strtok(NULL, ",");
-			}
-		}
-	}
+          options = add_option(opt, options);
+        }
+        opt = strtok(NULL, ",");
+      }
+    }
+  }
 
-	if (dev)
-		options = add_option("dev", options);
-	if (suid)
-		options = add_option("suid", options);
+  if (dev)
+    options = add_option("dev", options);
+  if (suid)
+    options = add_option("suid", options);
 
-	if (!type) {
-		if (source) {
-			type = xstrdup(source);
-			source = strchr(type, '#');
-			if (source)
-				*source++ = '\0';
-			if (!type[0]) {
-				fprintf(stderr, "%s: empty filesystem type\n",
-					progname);
-				exit(1);
-			}
-		} else {
-			fprintf(stderr, "%s: empty source\n", progname);
-			exit(1);
-		}
-	}
+  if (!type) {
+    if (source) {
+      type = xstrdup(source);
+      source = strchr(type, '#');
+      if (source)
+        *source++ = '\0';
+      if (!type[0]) {
+        fprintf(stderr, "%s: empty filesystem type\n",
+                progname);
+        exit(1);
+      }
+    } else {
+      fprintf(stderr, "%s: empty source\n", progname);
+      exit(1);
+    }
+  }
 
-	add_arg(&command, type);
-	if (source)
-		add_arg(&command, source);
-	add_arg(&command, mountpoint);
-	if (options) {
-		add_arg(&command, "-o");
-		add_arg(&command, options);
-	}
+  add_arg(&command, type);
+  if (source)
+    add_arg(&command, source);
+  add_arg(&command, mountpoint);
+  if (options) {
+    add_arg(&command, "-o");
+    add_arg(&command, options);
+  }
 
-	if (setuid && setuid[0]) {
-		char *sucommand = command;
-		command = NULL;
-		add_arg(&command, "su");
-		add_arg(&command, "-");
-		add_arg(&command, setuid);
-		add_arg(&command, "-c");
-		add_arg(&command, sucommand);
-	} else if (!getenv("HOME")) {
-		/* Hack to make filesystems work in the boot environment */
-		setenv("HOME", "/root", 0);
-	}
+  if (setuid && setuid[0]) {
+    char *sucommand = command;
+    command = NULL;
+    add_arg(&command, "su");
+    add_arg(&command, "-");
+    add_arg(&command, setuid);
+    add_arg(&command, "-c");
+    add_arg(&command, sucommand);
+  } else if (!getenv("HOME")) {
+    /* Hack to make filesystems work in the boot environment */
+    setenv("HOME", "/root", 0);
+  }
 
-	execl("/bin/sh", "/bin/sh", "-c", command, NULL);
-	fprintf(stderr, "%s: failed to execute /bin/sh: %s\n", progname,
-		strerror(errno));
-	return 1;
+  execl("/bin/sh", "/bin/sh", "-c", command, NULL);
+  fprintf(stderr, "%s: failed to execute /bin/sh: %s\n", progname,
+          strerror(errno));
+  return 1;
 }

man/mergerfs.1

@@ -12,16 +12,16 @@ is a FUSE-based union filesystem geared towards simplifying storage and manageme
 and
 .BR aufs .
 .SH QUICKSTART
-.UR https://trapexit.github.io/mergerfs/quickstart
-.LI https://trapexit.github.io/mergerfs/quickstart
+.UR https://trapexit.github.io/mergerfs/latest/quickstart
+.LI https://trapexit.github.io/mergerfs/latest/quickstart
 .UE
 .SH DOCUMENTATION
 .UR https://trapexit.github.io/mergerfs
 .LI https://trapexit.github.io/mergerfs
 .UE
 .SH SUPPORT
-.UR https://trapexit.github.io/mergerfs/support
-.LI https://trapexit.github.io/mergerfs/support
+.UR https://trapexit.github.io/mergerfs/latest/support
+.LI https://trapexit.github.io/mergerfs/latest/support
 .UE
 .SH FEATURES
 .IP \[bu] 2
@@ -74,8 +74,8 @@ When a file or directory is created, a policy is first run to determine which br
 For functions which change attributes or remove the file, the behavior may be applied to all instances found.
 
 Read more about policies here:
-.UR https://trapexit.github.io/mergerfs/config/functions_categories_and_policies
-.LI https://trapexit.github.io/mergerfs/config/functions_categories_and_policies
+.UR https://trapexit.github.io/mergerfs/latest/config/functions_categories_policies
+.LI https://trapexit.github.io/mergerfs/latest/config/functions_categories_policies
 .UE
 .SH VISUALIZATION
 .nf

mkdocs/docs/config/functions_categories_policies.md

@@ -116,6 +116,7 @@ but it makes things a bit more uniform.
 | mfs (most free space)                                           | Pick the branch with the most available free space.                                                                                                                             |
 | ff (first found)                                                | Given the order of the branches, as defined at mount time or configured at runtime, act on the first one found.                                                                 |
 | lfs (least free space)                                          | Pick the branch with the least available free space.                                                                                                                            |
+| lup (least used percent)                                        | Pick the branch with the least used percentage of space                                                                                                                         |
 | lus (least used space)                                          | Pick the branch with the least used space.                                                                                                                                      |
 | all                                                             | Search: For **mkdir**, **mknod**, and **symlink** it will apply to all branches. **create** works like **ff**.                                                                  |
 | msppfrd (most shared path, percentage free random distribution) | Like **eppfrd** but if it fails to find a branch it will try again with the parent directory. Continues this pattern till finding one.                                          |

mkdocs/docs/config/lazy-umount-mountpoint.md

@@ -0,0 +1,27 @@
+# lazy-umount-mountpoint
+
+* type: `BOOL`
+* default: `false`
+* example: `lazy-umount-mountpoint=true`
+
+When enabled mergerfs will issue a [lazy
+umount](https://man7.org/linux/man-pages/man8/umount.8.html) request
+to the mount point as it starts.
+
+```
+Lazy unmount. Detach the filesystem from the file hierarchy
+now, and clean up all references to this filesystem as soon as
+it is not busy anymore.
+```
+
+The value of using this is in situations where you wish to change
+options which can only be set at initialization or upgrade mergerfs
+itself. It also helps in the case of using `mount -a` which leads to a
+new instance of mergerfs being mounted due to it being unable to
+recognize that it is already mounted.
+
+In theory mergerfs could notice that an instance is already mounted at
+the mount point and attempt to use the runtime interface to modify the
+options and only mounting a new instance if the version has changed or
+initialization time only options are changed. However, given the
+relative rarity of this being an issue it isn't a priority.

mkdocs/docs/config/options.md

@@ -213,17 +213,14 @@ config file.
 * **passthrough.max-stack-depth=INT**: Set to `1` another filesystem
   can be stacked on mergerfs. Set to `2` to have mergerfs stacked over
   another filesystem. (default: 1)
-* **gid-cache.expire-timeout=INT**: Number of seconds till
-  supplemental group data is refreshed in the [GID
-  cache](../known_issues_bugs.md#supplemental-user-groups). (default:
-  3600)
-* **gid-cache.remove-timeout=INT**: Number of seconds to wait till
-  cached data is removed due to lack of usage. (default: 43200)
 * **remember-nodes=INT**: The number of seconds to keep the internal
   representation of a file once the OS tells mergerfs it is no longer
   needed. Really only needed for [exporting mergerfs via
   NFS](../remote_filesystems.md) (default: 0)
 * **noforget**: Effectively sets `remember-nodes` to infinity.
+* **allow-idmap=BOOL**: Enables idmap (identity mapping). (default:
+  true)
+
 
 **NOTE:** Options are evaluated in the order listed so if the options
 are **func.rmdir=rand,category.action=ff** the **action** category

mkdocs/docs/faq/compatibility_and_integration.md

@@ -5,16 +5,10 @@
 [Primarily Linux.](../setup/installation.md) FreeBSD is casually
 supported but not well tested.
 
-With FreeBSD certain Linux functions and FUSE features are not
-supported. In many cases the absense will not be noticed however
-performance may be impacted due to a core mergerfs design decision
-relying on a Linux feature.
-
-Linux allows individual threads to change credentials whereas [FreeBSD
-does not](https://wiki.freebsd.org/Per-Thread%20Credentials). As a
-result mergerfs must use a lock to ensure critical sections which need
-to change credentials are safeguarded. This will limit throughput on
-systems where requests to mergerfs come from multiple user identities.
+With FreeBSD certain Linux functions and FUSE features [are not
+supported.](../known_issues_bugs.md#freebsd-version) In many cases the
+absence will not be noticed however more advanced features will not be
+available.
 
 
 ### Why not support MacOS?
@@ -36,29 +30,47 @@ level API.
 
 Windows, while used for NAS systems more often than MacOS, is still
 relatively uncommon when compared to Linux. [Drive
-Pool](../project_comparisons.md#stablebits-drivepool) is a reasonable
-alternative.
+Pool](../project_comparisons.md#stablebits-drivepool) is a good
+alternative. It may also be possible to use mergerfs with WSL.
 
 
 ## What filesystems can be used as branches?
 
 ext4, btrfs, xfs, f2fs, zfs, nfs, etc.
 
-On the surface any filesystem should work but there could be issues
-with non-POSIX compliant filesystems such as vfat, ntfs, cifs, exfat,
-etc. When directories need to be created or files moved by mergerfs if
-the filesystem returns errors due to not supporting certain POSIX
-filesystem features it could result in the core functions failing.
+Most any filesystem should work but there could be issues with
+non-POSIX compliant filesystems such as nfs (w/ root squashing), vfat,
+ntfs, cifs, exfat, etc. When directories need to be created or files
+moved by mergerfs if the filesystem returns errors due to not
+supporting certain POSIX filesystem features it could result in the
+core functions failing.
 
 Since mergerfs is not generally used with non-POSIX filesystems this
 has not been a problem for users and there are some checks for known
-edgecases but it is possible some are not accounted for. If use with a
+edge cases but it is possible some are not accounted for. If use with a
 filesystem results in issues please [file a
 ticket](https://github.com/trapexit/mergerfs/issues) with the details.
 
 
+## What types of storage devices does mergerfs work with?
+
+Since mergerfs works at the filesystem level rather than device level
+there is no compatibility concerns based on the physical storage
+devices involved.
+
+
 ## Can I use mergerfs without SnapRAID? SnapRAID without mergerfs?
 
+[https://www.snapraid.it](https://www.snapraid.it)
+
+Yes. They are completely unrelated pieces of software that just happen
+to work well together.
+
+
+## Can I use mergerfs without nonraid? nonraid without mergerfs?
+
+[https://github.com/qvr/nonraid](https://github.com/qvr/nonraid)
+
 Yes. They are completely unrelated pieces of software that just happen
 to work well together.
 
@@ -80,16 +92,8 @@ pool.
 
 ## Can mergerfs run via Docker, Podman, Kubernetes, etc.
 
-Yes. With Docker you'll need to include `--cap-add=SYS_ADMIN
---device=/dev/fuse --security-opt=apparmor:unconfined` or similar with
-other container runtimes. You should also be running it as root or
-given sufficient caps to allow mergerfs to change user and group
-identity as well as have root like filesystem permissions. This
-ability is critical to how mergerfs works.
-
-Also, as mentioned by [hotio](https://hotio.dev/containers/mergerfs),
-with Docker you should probably be mounting with `bind-propagation`
-set to `slave`.
+Yes. [See installation
+page.](../setup/installation.md#podman-docker-oci-containers)
 
 
 ## How does mergerfs interact with user namespaces?

mkdocs/docs/faq/configuration_and_policies.md

@@ -29,6 +29,17 @@ If it isn't clear to you then you should use `pfrd` as described in
 the [quickstart guide](../quickstart.md).
 
 
+## Why are there no policies based on file size?
+
+Because it is not possible to know the final size of a file at creation
+time.
+
+See [How does mergerfs handle moving and copying of
+files?](technical_behavior_and_limitations.md#how-does-mergerfs-handle-moving-and-copying-of-files)
+and [Intro to Filesystems - Creating a
+file](../intro_to_filesystems.md#creating-a-file).
+
+
 ## Why is pfrd the default create policy?
 
 Originally the default was `epmfs` however it was found to cause

mkdocs/docs/faq/recommendations_and_warnings.md

@@ -1,56 +0,0 @@
-# Recommendations and Warnings
-
-## What should mergerfs NOT be used for?
-
-* Situations where you need large amounts of contiguous space beyond
-  that available on any singular device. Such as putting 10GiB file on
-  2 6GiB filesystems.
-* databases: Even if the database stored data in separate files
-  (mergerfs wouldn't offer much otherwise) the higher latency of the
-  indirection will really harm performance. If it is a lightly used
-  sqlite3 database then it should be fine.
-* VM images: For the same reasons as databases. VM images are accessed
-  very aggressively and mergerfs will introduce a lot of extra latency.
-* As replacement for RAID: mergerfs is just for pooling branches. If
-  you need device performance aggregation or high availability you
-  should stick with RAID. However, it is fine to put a filesystem
-  which is on a RAID setup in mergerfs.
-  
-**However, if using [passthrough](../config/passthrough.md) the
-performance related issues above are less likely to be a concern. Best
-to do testing for your specific use case.**
-
-
-## It's mentioned that there are some security issues with mhddfs. What are they? How does mergerfs address them?
-
-[mhddfs](https://github.com/trapexit/mhddfs) manages running as
-`root` by calling
-[getuid()](https://github.com/trapexit/mhddfs/blob/cae96e6251dd91e2bdc24800b4a18a74044f6672/src/main.c#L319)
-and if it returns `0` then it will
-[chown](http://linux.die.net/man/1/chown) the file. Not only is that a
-race condition but it doesn't handle other situations. Rather than
-attempting to simulate POSIX ACL behavior the proper way to manage
-this is to use [seteuid](http://linux.die.net/man/2/seteuid) and
-[setegid](http://linux.die.net/man/2/setegid), in effect, becoming the
-user making the original call, and perform the action as them. This is
-what mergerfs does and why mergerfs should always run as root.
-
-In Linux setreuid syscalls apply only to the thread. glibc hides this
-away by using realtime signals to inform all threads to change
-credentials. Taking after Samba, mergerfs uses
-`syscall(SYS_setreuid,...)` to set the callers credentials for that
-thread only. Jumping back to `root` as necessary should escalated
-privileges be needed (for instance: to clone paths between
-filesystems).
-
-For non-Linux systems, mergerfs uses a read-write lock and changes
-credentials only when necessary. If multiple threads are to be user X
-then only the first one will need to change the processes
-credentials. So long as the other threads need to be user X they will
-take a readlock allowing multiple threads to share the
-credentials. Once a request comes in to run as user Y that thread will
-attempt a write lock and change to Y's credentials when it can. If the
-ability to give writers priority is supported then that flag will be
-used so threads trying to change credentials don't starve. This isn't
-the best solution but should work reasonably well assuming there are
-few users.

mkdocs/docs/faq/technical_behavior_and_limitations.md

@@ -68,6 +68,11 @@ underlying data. For more details as to why that is see the docs on
 [inodecalc](../config/inodecalc.md).
 
 
+## Are there any size limitations to files, directories, etc.?
+
+Whatever the limits are of the underlying filesystems.
+
+
 ## Do reflink, FICLONE, or FICLONERANGE work?
 
 Unfortunately not. FUSE, the technology mergerfs is based on, does not
@@ -146,7 +151,7 @@ You can remove the reserve by running: `tune2fs -m 0 <device>`
 
 ## I notice massive slowdowns of writes when enabling cache.files.
 
-When file caching is enabled in any form (`cache.files!=off`) it will
+When file caching is enabled in any form (`cache.files!=off`) it may
 issue `getxattr` requests for `security.capability` prior to _every
 single write_. This will usually result in performance degradation,
 especially when using a network filesystem (such as NFS or SMB.)
@@ -178,20 +183,21 @@ disadvantages to each one.
 
 A FUSE based solution has all the downsides of FUSE:
 
-- Higher IO latency due to the trips in and out of kernel space
-- Higher general overhead due to trips in and out of kernel space
-- Double caching when using page caching
-- Misc limitations due to FUSE's design
+* Higher IO latency due to the trips in and out of kernel space
+  (though now minimized with passthrough IO)
+* Higher general overhead due to trips in and out of kernel space
+* Double caching when using page caching
+* Misc limitations due to FUSE's design
 
 But FUSE also has a lot of upsides:
 
-- Easier to offer a cross platform solution
-- Easier forward and backward compatibility
-- Easier updates for users
-- Easier and faster release cadence
-- Allows more flexibility in design and features
-- Overall easier to write, secure, and maintain
-- Much lower barrier to entry (getting code into the kernel takes a
+* Easier to offer a cross platform solution
+* Easier forward and backward compatibility
+* Easier updates for users
+* Easier and faster release cadence
+* Allows more flexibility in design and features
+* Overall easier to write, secure, and maintain
+* Much lower barrier to entry (getting code into the kernel takes a
   lot of time and effort initially)
 
 
@@ -220,45 +226,56 @@ removed to simplify the codebase.
 
 ## How does mergerfs handle credentials?
 
-
 mergerfs is a multithreaded application in order to handle requests
 from the kernel concurrently. Each FUSE message has a header with
 certain details about the request including the process ID (pid) of
 the requesting application, the process' effective user id (uid), and
-group id (gid). To ensure proper POSIX filesystem behavior and
-security mergerfs must change its identity to match that of the
-requester when performing the certain functions on the underlying
-filesystem. As required by standards most Unix/POSIX based systems a
-process and all its threads are under the same uid and gid. However,
-on Linux each thread **may** have its own credentials. This allows
-mergerfs to be multithreaded and for each thread to change to the
-credentials as required by the incoming message it is
-handling. However, currently on FreeBSD this is not possible (though
-there has been
-[discussions](https://wiki.freebsd.org/Per-Thread%20Credentials)) and
-as such must change the credentials of the whole application when
-actioning messages. mergerfs does optimize this behavior by only
-changing credentials and locking the thread to do so if the process is
-currently not the same as what is necessary by the incoming
-request. As a result of this design FreeBSD may experience more
-contention and therefore lower performance than Linux.
+group id (gid).
 
-Additionally, mergerfs [utilizes a cache for supplemental
-groups](../known_issues_bugs.md#supplemental-user-groups) due the the
-high cost of querying that information.
+FUSE and the kernel have two ways of managing permissions. A kernel
+side `default_permissions` option and leaving it to the FUSE
+server. When default permissions is enabled the kernel will do the
+entitlement checks and only allow requests through which should be
+allowed according to normal POSIX permissions. When not enabled it is
+the responsibility of the FUSE server, in this case mergerfs, to do
+whatever is necessary to manage entitlements.
+
+Prior to mergerfs v2.42.0 it would enable `default_permissions` but
+also leveraged the uid and gid available in each FUSE request. The
+thread actioning the request would change its credentials to match
+those of the requesting application to ensure permissions were
+properly handled as well as dealing with some quirks of non-POSIX
+compatible filesystems. However, this strategy had two major
+issues. First, it was not compatible with the new `allow-idmap`
+feature of FUSE which allows a filesystem to advertise it can be used
+with id mapping which is often used with containers. Secondly, it
+caused permission issues when the kernel would say something was
+allowed but due to the way mergerfs was changing creds would
+fail. This mostly came in the form of `chroot`ed setups like used in
+containers. Neither of these tended to impact casual users but did
+break some niche or power user use cases. Since the casual user won't
+notice the subtle changes and it would enable new use cases it was
+decided that the credential handling would change.
+
+As of v2.42.0 mergerfs now runs as root more generally. Either
+changing credentials when creating files (Linux) or chown'ing them
+after creation (FreeBSD).
+
+As a result of this change it is now necessary for the FUSE
+`default_permissions` feature be used for proper entitlements
+management. mergerfs does allow it to be disabled but it should only
+be done so for debugging purposes.
 
 
 ## Does mergerfs support idmap?
 
-Yes. At least in so far as it's been enabled now the FUSE itself
-allows a filesystem to indicate it is allowed.
+Yes, by setting [allow-idmap=true](../config/options.md) (which is the
+default.)
 
 Requires that
 [kernel-permissions-check](../config/kernel-permissions-check.md) be
 enabled (the default.)
 
-If there are any usage issues contact the [author](../support.md).
-
 
 ## What happens if a branch filesystem blocks?
 
@@ -282,3 +299,8 @@ Every incoming request contains:
 
 Naturally the mergerfs config as well as anything queriable from the
 operating system or filesystems are also available.
+
+
+## Why does running `mount -a` result in new instances of mergerfs?
+
+See [lazy-umount-mountpoint](../config/lazy-umount-mountpoint.md)

mkdocs/docs/faq/usage_and_functionality.md

@@ -1,5 +1,26 @@
 # Usage and Functionality
 
+## What should mergerfs NOT be used for?
+
+* Situations where you need large amounts of contiguous space beyond
+  that available on any singular device. Such as putting 10GiB a file
+  on 2 6GiB filesystems.
+* databases: Even if the database stored data in separate files
+  (mergerfs wouldn't offer much otherwise) the higher latency of the
+  indirection will harm performance. Though if it is a sqlite3
+  database then its likely fine.
+* VM images: For the same reasons as databases. VM images are accessed
+  very aggressively and mergerfs will introduce a lot of extra latency.
+* As replacement for RAID: mergerfs is just for pooling branches. If
+  you need device performance aggregation or high availability you
+  should stick with RAID. However, it is fine to put a filesystem
+  which is on a RAID setup in mergerfs.
+
+**However, if using [passthrough](../config/passthrough.md) the
+performance related issues above are less likely to be a concern. Best
+to do testing for your specific use case.**
+
+
 ## What happens when file paths overlap?
 
 It depends on the situation and the configuration of mergerfs. The

mkdocs/docs/index.md

@@ -1,14 +1,44 @@
 # mergerfs - a featureful union filesystem
 
-**mergerfs** is a
-[FUSE](https://en.wikipedia.org/wiki/Filesystem_in_Userspace) based
-[union filesystem](https://en.wikipedia.org/wiki/Union_mount) geared
-towards simplifying storage and management of files across numerous
-commodity storage devices. It is similar to [**mhddfs**, **unionfs**,
-**aufs**, **DrivePool**, etc.](project_comparisons.md) Allowing for
-the aggregation of storage without the more rigid requirements and
-failure conditions of [RAID and other
-technologies](project_comparisons.md).
+**mergerfs** is a [union
+filesystem](https://en.wikipedia.org/wiki/Union_mount) that makes
+multiple filesystems and/or directories appear as a single unified
+directory. mergerfs is designed to simplify how you manage files
+across multiple independent filesystems without the complexity,
+fragility, or cost of RAID or similar storage aggregation
+technologies.
+
+mergerfs as a smart pooling layer allows you to combine any number of
+[existing
+filesystems](faq/usage_and_functionality.md#can-mergerfs-be-used-with-filesystems-which-already-have-data);
+whether they are on hard drives, SSDs, network shares, or other
+mounted storage; into what looks like one large filesystem, while
+still maintaining direct access to each individual filesystem. Unlike
+RAID, there's no rebuild process if a device fails. You only lose
+those files that were on that specific filesystem. You can also add or
+remove filesystems at any time without restructuring the pool.
+
+mergerfs excels at cost-effective storage expansion, making it ideal
+for media libraries, backups, archival data, and other write-sometimes,
+read-often workloads where you need lots of space but don't want
+the overhead of traditional storage aggregation technologies.
+
+**Key advantages:**
+
+* Mix and match filesystems of any size,
+  [type](faq/compatibility_and_integration.md#what-filesystems-can-be-used-as-branches),
+  or [underlying
+  device](faq/compatibility_and_integration.md#what-types-of-storage-devices-does-mergerfs-work-with)
+* No parity calculations or rebuild times
+* Does not require hard drives to be spinning if not in use
+* Add or remove filesystems on the fly
+* [Direct access to files](faq/usage_and_functionality.md#can-filesystems-still-be-used-directly-outside-of-mergerfs-while-pooled) on individual filesystems when needed
+* Flexible [policies](config/functions_categories_policies.md) for controlling where new files are created
+
+For users seeking alternatives to mhddfs, unionfs, aufs, or DrivePool,
+mergerfs offers a mature, actively maintained solution with extensive
+configuration options and documentation. See the [project comparisons
+for more details.](project_comparisons.md)
 
 
 ## Features
@@ -19,7 +49,7 @@ technologies](project_comparisons.md).
 * Ability to add or remove filesystems/paths without impacting the
   rest of the data
 * Unaffected by individual filesystem failure
-* Configurable file selection and creation placement
+* Configurable file creation placement
 * File IO [passthrough](config/passthrough.md) for near native IO
   performance (where supported)
 * Works with filesystems of any size
@@ -28,7 +58,7 @@ technologies](project_comparisons.md).
 * Ignore read-only filesystems when creating files
 * [Hard links](faq/technical_behavior_and_limitations.md#do-hard-links-work)
 * Hard link [copy-on-write / CoW](config/link-cow.md)
-* [Runtime configurable](runtime_interface.md)
+* [Runtime configurability](runtime_interface.md)
 * Support for extended attributes (xattrs)
 * Support for file attributes (chattr)
 * Support for POSIX ACLs
@@ -36,19 +66,22 @@ technologies](project_comparisons.md).
 
 ## Non-features
 
-* Read/write overlay on top of read-only filesystem like OverlayFS
-* File whiteout
 * RAID like redundancy (see [SnapRAID](https://www.snapraid.it) and
   [NonRAID](https://github.com/qvr/nonraid))
-* Redundancy
+* LVM/RAID style block device aggregation
+* Data integrity checks, snapshots, file versioning
+* Read/write overlays on top of read-only filesystems (like OverlayFS)
+* File whiteout
 * Splitting of files across branches
+* Active rebalancing of content
+* [Actively attempt to keep hard drives spun down](faq/limit_drive_spinup.md)
 
 
 ## How it works
 
 mergerfs logically merges multiple filesystem paths together. Not
 block devices, not filesystem mounts, just paths. It acts as a proxy
-to the underlying filesystem paths. Combining the behaviors of some
+to the underlying filesystem. Combining the behaviors of some
 functions and being a selector for others.
 
 When the contents of a directory are requested mergerfs combines the
@@ -62,7 +95,7 @@ For functions which change attributes or remove the file the behavior
 may be applied to all instances found.
 
 The way in which mergerfs behaves is controlled by the
-[config/options/settings](config/options.md). More specifically by
+[config / options / settings](config/options.md). More specifically by
 [policies](config/functions_categories_policies.md).
 
 
@@ -90,7 +123,6 @@ A         +      B        =       C
 +-- file7        +-- file7        +-- file7
 ```
 
-
 ## Getting Started
 
 Head to the [quick start guide](quickstart.md).
@@ -107,3 +139,9 @@ Head to the [quick start guide](quickstart.md).
   like something is not explained sufficiently or missing please [ask
   in one of the supported forums](support.md#contact-issue-submission)
   and the docs will be updated.
+* The search feature of MkDocs is not great. Searching for "literal
+  strings" will generally not work. Alernative solutions are being
+  investigated.
+* While not intended for end users nor completely accurate some might
+  find the AI generated docs at https://deepwiki.com/trapexit/mergerfs
+  interesting or useful.

mkdocs/docs/known_issues_bugs.md

@@ -4,10 +4,17 @@
 
 ### FreeBSD version
 
-* FreeBSD doesn't have per thread credentials meaning threads must
-  block to change credentials as required by numerous filesystem
-  functions. This impacts performance.
-* FreeBSD's FUSE implementation is lacking many features of Linux.
+* [https://wiki.freebsd.org/FUSEFS](https://wiki.freebsd.org/FUSEFS)
+* FreeBSD does not have per thread credentials nor Linux capabilities
+  like abilities meaning it runs as root and has to create files as
+  root then chown them rather than changing credentials and creating
+  the file as the uid:gid.
+* FreeBSD does not have `getdents` like APIs for reading
+  directories. As a result it uses traditional `readdir`.
+* FreeBSD's FUSE implementation is lacking many features of the Linux
+  version.
+    * runtime interface
+    * ioctl support
     * IO passthrough
     * statx
     * lazy umount
@@ -16,26 +23,10 @@
     * kernel symlink caching
     * kernel readdir caching
     * writeback caching
+    * idmap
     * ...
 
 
-### Supplemental user groups
-
-#### Supplemental group caching
-
-Due to the high cost of querying supplemental groups it is necessary
-for mergerfs to cache the list. As a result if supplemental groups are
-changed while mergerfs is running the cache may become stale. This
-generally isn't a problem as these groups tend not to be changed
-often. However, the cache has a default expiry of 1 hour and after 12
-hours of no usage the cache entry will be removed altogether.
-
-See [gidcache.expire-timeout and
-gid-cache.remove-timeout](config/options.md) and the [runtime
-interface](runtime_interface.md#commands) for forcing expiry and clearing of
-the cache.
-
-
 #### Host vs Container identity
 
 While not a bug some users have found when using containers that
@@ -99,9 +90,9 @@ on [page caching](config/cache.md).
 ### Software using mmap
 
 * software using sqlite3 w/ mmap
-    * Plex (for config)
-    * Jellyfin (for config)
-    * Emby (for config)
+    * Plex (for config, not media)
+    * Jellyfin (for config, not media)
+    * Emby (for config, not media)
     * Radarr
     * Sonarr
     * Lidarr
@@ -113,17 +104,26 @@ on [page caching](config/cache.md).
 operating system feature allowing files to be interacted with as if it
 was normal memory. Support for `mmap` is **required** by a number of
 projects. FUSE (and therefore mergerfs), in order to support `mmap`,
-requires [page caching](config/cache.md) to be
-enabled. IE `cache.files` must not be set to `off` (if using Linux before
-v6.6 or mergerfs before v2.41.0.)
+requires [page caching](config/cache.md) to be enabled. IE
+`cache.files` must not be set to `off` (if using Linux before v6.6 or
+mergerfs before v2.41.0.) In newer versions of mergerfs and Linux
+`off` will work as it can now auto enable page caching (and therefore
+`mmap`) as needed.
 
-In newer versions of mergerfs and Linux `off` will work as it can now
-auto enable page caching (and therefore `mmap`) as needed.
+When `mmap` is needed but not available you may see `ENODEV` or `No
+such device` errors though it will depend on the particular software.
+
+Details on enabling `mmap` can be found at:
+
+* [QuickStart](quickstart.md#configuration)
+* [Config > cache.files](config/cache.md#cachefiles)
 
 That said it is recommended that config and runtime files be stored on
 SSDs on a regular filesystem for performance reasons. See [What should
 mergerfs NOT be used
-for?](faq/recommendations_and_warnings.md#what-should-mergerfs-not-be-used-for).
+for?](faq/usage_and_functionality.md#what-should-mergerfs-not-be-used-for). Though
+with [passthrough.io](config/passthrough.md) enabled that is less
+of a concern.
 
 Technically **sqlite3** does not require `mmap`, and in fact the
 default is not to use it, but many programs enable the feature and
@@ -133,6 +133,25 @@ more compatible but could also be more performant in certain
 situations.
 
 
+### qbittorrent
+
+Same `mmap` concerns as mentioned above but called out specifically
+due to regularity of queries.
+
+The default "Disk IO type" setting is "Memory mapped files" which
+means it requires `mmap` support.
+
+If qbittorrent errors when using mergerfs ensure that either "Disk IO
+type" is set to "POSIX-compliant" or "Simple pread/pwrite"; or setup
+mergerfs to support `mmap`.
+
+References:
+
+* [Software using mmap](#software-using-mmap)
+* [QuickStart](quickstart.md#configuration)
+* [Config > cache.files](config/cache.md#cachefiles)
+
+
 ### rsync
 
 This isn't specific to mergerfs but when using `--sparse, -S` option

mkdocs/docs/performance.md

@@ -1,15 +1,17 @@
 # Tweaking Performance
 
-`mergerfs` is effectively a filesystem proxy and therefore its
+**mergerfs** is effectively a filesystem proxy and therefore its
 theoretical max performance is that of the underlying devices
 (ignoring caching performed by the kernel.) However, given it is a
-FUSE based filesystem working from userspace there is an increase in
-overhead relative to kernel based solutions. That said the performance
-can match the theoretical max but it depends greatly on the system's
+FUSE based filesystem working from userspace and it must combine the
+behavior and information from multiple underlying branches there can
+be an increase in overhead relative to other solutions. That said the
+performance of certain functions, such as IO, can match the
+theoretical max but it depends greatly on the system's
 configuration. There are many things which can impact
 performance. Device speeds and latency, network speeds and latency,
-concurrency and parallel limits of the hardware, read/write sizes,
-etc.
+concurrency and parallel limits of the hardware, read/write sizes, the
+number of branches, etc.
 
 While some settings can impact performance they are all **functional**
 in nature. Meaning they change mergerfs' behavior in some way. As a
@@ -27,7 +29,7 @@ before changing them to understand how functionality will change.
 * enable [passthrough.io](config/passthrough.md) (likely to have the
   biggest impact)
 * change read or process [thread pools](config/threads.md)
-* toggle [func.readdir](config/func_readdir.md)
+* change [func.readdir](config/func_readdir.md)
 * increase [readahead](config/readahead.md): `readahead=1024`
 * disable `security-capability` and/or [xattr](config/xattr.md)
 * increase cache timeouts [cache.attr](config/cache.md#cacheattr),

mkdocs/docs/project_comparisons.md

@@ -7,11 +7,13 @@ There are no solutions, only trade-offs.
 
 * [https://romanrm.net/mhddfs](https://romanrm.net/mhddfs)
 
+mhddfs is, like mergerfs, a FUSE based filesystem which can pool
+multiple filesystems together.
+
 mhddfs had not been updated in over a decade and has known stability
 and security issues. mergerfs provides a super set of mhddfs' features
-and offers better performance. In fact, as of 2020, the author of
-mhddfs has [moved to using
-mergerfs.](https://romanrm.net/mhddfs#update)
+and offers better performance. As of 2020 the author of mhddfs has
+[moved to using mergerfs.](https://romanrm.net/mhddfs#update)
 
 Below is an example of mhddfs and mergerfs setup to work similarly.
 
@@ -25,14 +27,18 @@ Below is an example of mhddfs and mergerfs setup to work similarly.
 * [https://aufs.sourceforge.net](https://aufs.sourceforge.net)
 * [https://en.wikipedia.org/wiki/Aufs](https://en.wikipedia.org/wiki/Aufs)
 
+aufs, another union filesystem, is a kernel based overlay filesystem
+with basic file creation placement policies.
+
 While aufs still is maintained it failed to be included in the
 mainline kernel and is no longer available in most Linux distros
 making it harder to get installed for the average user.
 
 While aufs can often offer better peak performance due to being
-primarily kernel based, mergerfs provides more configurability and is
-generally easier to use. mergerfs however does not offer the overlay /
-copy-on-write (CoW) features which aufs has.
+primarily kernel based (at least when `passthrough.io` is disabled),
+mergerfs provides more configurability and is generally easier to
+use. mergerfs however does not offer the overlay / copy-on-write (CoW)
+features which aufs has.
 
 
 ## unionfs
@@ -40,7 +46,7 @@ copy-on-write (CoW) features which aufs has.
 * [https://unionfs.filesystems.org](https://unionfs.filesystems.org)
 
 unionfs for Linux is a "stackable unification file system" which
-functions like many other union filesystems. unionfs has not been
+functions like many other union filesystems. unionfs is no longer
 maintained and was last released for Linux v3.14 back in 2014.
 
 Documentation is sparse so a comparison of features is not possible
@@ -101,7 +107,7 @@ aggregate their storage. The failure of any one device will have no
 impact on the other devices. The downside to mergerfs' technique is
 the fact you don't actually have contiguous space as large as if you
 used those other technologies. Meaning you can't create a file greater
-than 1TB on a pool of 2 1TB filesystems.
+than 1TB on a pool of two 1TB filesystems.
 
 
 ## BTRFS Single Data Profile
@@ -118,15 +124,20 @@ some abilities to recover data but this is not guaranteed.
 * [RAID5](https://en.wikipedia.org/wiki/Standard_RAID_levels#RAID_5)
 * [RAID6](https://en.wikipedia.org/wiki/Standard_RAID_levels#RAID_6)
 
+RAID5, RAID6, and similar technologies aggregate multiple devices at
+the block level and offer 1 or more live parity calculations that can
+allow the pool to continue to run should 1 device fail and rebuild the
+data once the device is replaced.
+
 mergerfs offers no parity or redundancy features so in that regard the
 technologies are not comparable. [SnapRAID](https://www.snapraid.it)
-can be used in combination with mergerfs to provide redundancy. Unlike
-traditional RAID5 or RAID6 SnapRAID works with drives of different
-sizes and can have more than 2 parity drives. However, parity
-calculations are not done in real-time.
+or [nonraid](https://github.com/qvr/nonraid) can be used in
+combination with mergerfs to provide redundancy. Unlike traditional
+RAID5 or RAID6 SnapRAID works with drives of different sizes and can
+have more than 2 parity drives. However, parity calculations are not
+done in real-time. However, nonraid is realtime.
 
-See [https://www.snapraid.it/compare](https://www.snapraid.it/compare)
-for more details and comparisons.
+For more details and comparison of SnapRAID to related technologies see [https://www.snapraid.it/compare](https://www.snapraid.it/compare).
 
 
 ## UnRAID
@@ -141,7 +152,9 @@ calculation can have higher peak performance. Some users also prefer
 an open source solution.
 
 For semi-static data mergerfs + [SnapRAID](http://www.snapraid.it)
-provides a similar, but not real-time, solution.
+provides a similar, but not real-time, solution. NonRAID (see below)
+is a fork of UnRAID's parity calculation solution and can also be used
+with mergerfs.
 
 
 ## NonRAID
@@ -163,6 +176,9 @@ be used with mergerfs for those looking for a unified view.
 
 * [https://en.wikipedia.org/wiki/ZFS](https://en.wikipedia.org/wiki/ZFS)
 
+ZFS is an advanced filesystem with many features including RAID5/6
+like redundency.
+
 mergerfs is very different from ZFS. mergerfs is intended to provide
 flexible pooling of arbitrary filesystems (local or remote), of
 arbitrary sizes, and arbitrary filesystems. Particularly in `write
@@ -173,6 +189,10 @@ can introduce a number of costs and limitations as described
 [here](https://markmcb.com/2020/01/07/five-years-of-btrfs/), and
 [here](https://utcc.utoronto.ca/~cks/space/blog/solaris/ZFSWhyNoRealReshaping).
 
+That said given mergerfs' flexibility it is common to see it used in
+combination with ZFS where critical data is written to a RAIDZ pool
+and bulk media stored on traditional filesystems pooled via mergerfs.
+
 
 ## ZFS AnyRAID
 
@@ -191,9 +211,9 @@ and there are no timelines or estimates for when it may be released.
 
 * [https://stablebit.com](https://stablebit.com)
 
-DrivePool works only on Windows so not as common an alternative as
-other Linux solutions. If you want to use Windows then DrivePool is a
-good option. Functionally the two projects work a bit
+DrivePool is a commercial filesystem pooling technology for
+Windows. If you are looking to use Windows then DrivePool is a good
+option. Functionally the two projects work a bit
 differently. DrivePool always writes to the filesystem with the most
 free space and later rebalances. mergerfs does not currently offer
 rebalance but chooses a branch at file/directory create
@@ -202,15 +222,12 @@ and has file pattern matching to further customize the
 behavior. mergerfs, not having rebalancing does not have these
 features, but similar features are planned for mergerfs v3. DrivePool
 has builtin file duplication which mergerfs does not natively support
-(but can be done via an external script.)
+(but can be done via an external program.)
 
 There are a lot of misc differences between the two projects but most
 features in DrivePool can be replicated with external tools in
 combination with mergerfs.
 
-Additionally, DrivePool is a closed source commercial product vs
-mergerfs a ISC licensed open source project.
-
 
 ## Plan9 binds
 
@@ -218,10 +235,10 @@ mergerfs a ISC licensed open source project.
 
 Plan9 has the native ability to bind multiple paths/filesystems
 together to create a setup similar to simplified union
-filesystem. Such bind mounts choose files in a "first found" in the
-order they are listed similar to mergerfs' `ff` policy. Similar, when
-creating a file it will be created on the first directory in the
-union.
+filesystem. Such bind mounts choose files in a "first found" manner
+based on the order they are configured similar to mergerfs' `ff`
+policy. Similarly, when creating a file it will be created on the
+first directory in the union.
 
 Plan 9 isn't a widely used OS so this comparison is mostly academic.
 

mkdocs/docs/remote_filesystems.md

@@ -76,7 +76,7 @@ but if you run into problems it may be worth trying Samba/SMB.
 
 **mergerfs settings:**
 
-* `noforget` or `remember-nodes=SECONDS`
+* `never-forget-nodes=true` or `remember-nodes=SECONDS`
 * `inodecalc=path-hash`
 * `lazy-umount-mountpoint=false`
 

mkdocs/docs/resource_usage.md

@@ -11,7 +11,6 @@
     * 1MB+ pre reader thread + inflight processing for messages
       depending on [fuse-msg-size](config/fuse-msg-size.md)
     * buffers allocated temporarily for reading directories
-    * [gidcache](faq/technical_behavior_and_limitations.md#how-does-mergerfs-handle-credentials)
     * FUSE nodes
     * noforget forgotten nodes
 

mkdocs/docs/runtime_interface.md

@@ -143,8 +143,6 @@ allows a value.
 | user.mergerfs.cmd.gc | (empty) |Trigger a thorough garbage collection of certain pools of resources. The xattr value is not used. |
 | user.mergerfs.cmd.gc1 | (empty) | Trigger a simple garbage collection of certain pools of resources. This is also done on a timer. |
 | user.mergerfs.cmd.invalidate-all-nodes | (empty) | Attempts to invalidate FUSE file nodes. Primarily used for debugging. |
-| user.mergerfs.cmd.invalidate-gid-cache | (empty) | Invalidates all entries in gid cache. Primarily used for debugging but can also be useful in cases where gid supplemental groups change. |
-| user.mergerfs.cmd.clear-gid-cache | (empty) | Clears all entries in the gid cache. Primarily used for debugging but can also be useful in cases where gid supplemental groups change. |
 
 ```
 [trapexit:/mnt/mergerfs] $ setfattr -n user.mergerfs.cmd.gc /mnt/mergerfs/.mergerfs

mkdocs/docs/setup/installation.md

@@ -106,6 +106,7 @@ nix-env -iA nixos.mergerfs
 
 [Check your distro.](../related_projects.md#distributions-including-mergerfs)
 
+
 ## Static Linux Binaries
 
 If your distro does not package mergerfs there are static binaries
@@ -117,3 +118,34 @@ Get the tarball from the [releases page](https://github.com/trapexit/mergerfs/re
 wget https://github.com/trapexit/mergerfs/releases/download/<ver>/mergerfs-static-linux_<arch>.tar.gz
 sudo tar xvf mergerfs-static-linux_<arch>.tar.gz -C /
 ```
+
+## Podman, Docker, OCI Containers
+
+[https://github.com/trapexit/mergerfs/pkgs/container/mergerfs](https://github.com/trapexit/mergerfs/pkgs/container/mergerfs)
+
+```
+podman pull ghcr.io/trapexit/mergerfs:TAG
+# or
+docker pull ghcr.io/trapexit/mergerfs:TAG
+```
+
+### rootful container runtimes
+
+```
+docker run --device=/dev/fuse --cap-add=SYS_ADMIN -v /mnt/to-merge:/mnt/to-merge:rshared -v /mnt/mergerfs:/mnt/mergerfs:z,shared ghcr.io/trapexit/mergerfs:TAG -f '/mnt/to-merge/*' '/mnt/mergerfs'
+```
+
+* `--device=/dev/fuse`: Pass in host FUSE device.
+* `--cap-add=SYS_ADMIN`: Give proper permissions to mount.
+* `-v /mnt/mergerfs:/mnt/mergerfs:z,shared`: `z` and `shared` will
+  allow the mount to be shared between the container and host and
+  therefore other containers.
+* `-v /mnt/to-merge:/mnt/to-merge:rshared`: The mounts from the host
+  to merge within the container.
+
+
+### rootless container runtimes
+
+Not possible? `:shared` is not rejected but won't work the same with
+rootless. Podman doesn't allow the creation of pods with shared mount
+namespace in rootless mode.

mkdocs/docs/sponsorship_and_donations.md

@@ -1,4 +1,4 @@
-# Sponsorship and Donations
+# Sponsorship, Donations, Support Contracts
 
 [https://github.com/trapexit/support](https://github.com/trapexit/support)
 
@@ -12,6 +12,6 @@ and would like to support the project financially it would be very
 much appreciated.
 
 If you are using mergerfs commercially please consider sponsoring the
-project to ensure it continues to be maintained and receive
-updates. If custom features are needed feel free to [contact me
-directly](mailto:support@spawn.link).
+project or purchasing a support contract to ensure it continues to be
+maintained and receive updates. [Reach out for more
+details](mailto:support@spawn.link?subject=mergerfs+support+contract+inquiry).

mkdocs/docs/support.md

@@ -38,8 +38,8 @@ directly.](mailto:support@spawn.link)**
     * Are the client apps using mergerfs running in a container?
 * A `strace` of the app having problems:
     * `strace -fvTtt -s 256 -o /tmp/app.strace.txt <cmd>`
-* A `strace` of mergerfs while the program is trying to do whatever it
-  is failing to do:
+* A `strace` of mergerfs **while** the program is trying to do
+  whatever it is failing to do:
     * `strace -fvTtt -s 256 -p <mergerfsPID> -o /tmp/mergerfs.strace.txt`
 * **Precise** directions on replicating the issue. Do not leave
   **anything** out.

mkdocs/docs/tips_notes.md

@@ -6,7 +6,7 @@
   like something is not explained sufficiently please [file a
   ticket.](https://github.com/trapexit/mergerfs/issues)
 * If a `libfuse` argument is not listed it probably shouldn't be used
-  and are unsupported.
+  and is unsupported.
 * Ensure you're using the latest version. Especially before submitting
   bug reports.
 * Run mergerfs as `root`. mergerfs is designed and intended to be run
@@ -15,7 +15,7 @@
   seem to skip branches, you get strange permission errors, etc. be
   sure the underlying filesystems' permissions are all the same. Use
   `mergerfs.fsck` to audit the filesystem for out of sync permissions.
-* If you still have permission issues be sure you are using POSIX ACL
+* If you still have permission issues be sure you are using POSIX
   compliant filesystems. mergerfs doesn't generally make exceptions
   for FAT, NTFS, or other non-POSIX filesystem.
 * Unless using Linux v6.6 or above do **not** use `cache.files=off` if

mkdocs/generate-and-push-docs

@@ -6,20 +6,21 @@ current_branch="$(git branch --show-current)"
 mike delete --all --push --allow-empty --ignore-remote-status
 
 git checkout "master"
-mike deploy --push "preview" "master"
+mike deploy --push "latest" "master" --ignore-remote-status
 
 for tag in $(git tag -l | sort --version-sort --reverse)
 do
     if git ls-tree -r --name-only "${tag}" | grep -q 'mkdocs.yml'; then
         git checkout "${tag}"
-        mike deploy --push "${tag}"
+        mike deploy --push "${tag}" --ignore-remote-status
     fi
 done
 
-latest="$(git tag -l | sort --version-sort --reverse | head -n 1)"
-git checkout "${latest}"
-mike alias --push "${latest}" "latest"
+#latest="$(git tag -l | sort --version-sort --reverse | head -n 1)"
+#git checkout "${latest}"
+#mike alias --push "${latest}" "latest"
+#mike alias --push "latest" "latest"
 
-mike set-default --push "preview"
+mike set-default --push "latest" --ignore-remote-status
 
 git checkout "${current_branch}"

mkdocs/mkdocs.yml

@@ -95,6 +95,7 @@ nav:
   - config/flush-on-close.md
   - config/export-support.md
   - config/kernel-permissions-check.md
+  - config/lazy-umount-mountpoint.md
 - error_handling_and_logging.md
 - resource_usage.md
 - runtime_interface.md
@@ -112,7 +113,6 @@ nav:
   - faq/usage_and_functionality.md
   - faq/reliability_and_scalability.md
   - faq/compatibility_and_integration.md
-  - faq/recommendations_and_warnings.md
   - faq/technical_behavior_and_limitations.md
   - faq/have_you_considered.md
   - faq/limit_drive_spinup.md

src/atomicsharedptr.hpp

@@ -0,0 +1,108 @@
+#pragma once
+
+#include <memory>
+#include <utility>
+
+template<typename T>
+class AtomicSharedPtr
+{
+private:
+  std::shared_ptr<T> _ptr;
+
+public:
+  AtomicSharedPtr() = default;
+
+  explicit
+  AtomicSharedPtr(std::shared_ptr<T> ptr_)
+    : _ptr(std::move(ptr_))
+  {
+  }
+
+  template<typename... Args>
+  explicit
+  AtomicSharedPtr(Args&&... args)
+    : _ptr(std::make_shared<T>(std::forward<Args>(args)...))
+  {
+  }
+
+  AtomicSharedPtr(const AtomicSharedPtr&) = delete;
+  AtomicSharedPtr& operator=(const AtomicSharedPtr&) = delete;
+
+  AtomicSharedPtr(AtomicSharedPtr&& other_) noexcept
+    : _ptr(std::move(other_._ptr))
+  {
+  }
+
+  AtomicSharedPtr&
+  operator=(AtomicSharedPtr&& other_) noexcept
+  {
+    if(this != &other_)
+      _ptr = std::move(other_._ptr);
+
+    return *this;
+  }
+
+  std::shared_ptr<T>
+  load() const
+  {
+    return std::atomic_load(&_ptr);
+  }
+
+  void
+  store(std::shared_ptr<T> desired_)
+  {
+    std::atomic_store(&_ptr, std::move(desired_));
+  }
+
+  std::shared_ptr<T>
+  exchange(std::shared_ptr<T> desired_)
+  {
+    return std::atomic_exchange(&_ptr, std::move(desired_));
+  }
+
+  bool
+  compare_exchange_strong(std::shared_ptr<T>& expected_,
+                          std::shared_ptr<T>  desired_)
+  {
+    return std::atomic_compare_exchange_strong(&_ptr,
+                                               &expected_,
+                                               std::move(desired_));
+  }
+
+  bool
+  compare_exchange_weak(std::shared_ptr<T>& expected_,
+                        std::shared_ptr<T>  desired_)
+  {
+    return std::atomic_compare_exchange_weak(&_ptr,
+                                             &expected_,
+                                             std::move(desired_));
+  }
+
+  bool
+  is_null() const
+  {
+    return !std::atomic_load(&_ptr);
+  }
+
+  void
+  reset()
+  {
+    std::atomic_store(&_ptr, std::shared_ptr<T>());
+  }
+
+  T*
+  get() const
+  {
+    return std::atomic_load(&_ptr).get();
+  }
+
+  template<typename... Args>
+  auto
+  operator()(Args&&... args) const ->
+    decltype(std::declval<T>()(std::forward<Args>(args)...))
+  {
+    auto ptr = load();
+
+    return (*ptr)(std::forward<Args>(args)...);
+  }
+};

src/branch.hpp

@@ -18,7 +18,7 @@
 
 #pragma once
 
-#include "int_types.h"
+#include "base_types.h"
 #include "strvec.hpp"
 #include "tofrom_string.hpp"
 #include "fs_path.hpp"
@@ -52,6 +52,9 @@ public:
   Branch(const Branch&);
   Branch(const u64 &default_minfreespace);
 
+public:
+  Branch& operator=(const Branch&) = default;
+
 public:
   bool ro(void) const;
   bool nc(void) const;

src/branches.cpp

@@ -23,7 +23,7 @@
 #include "fs_glob.hpp"
 #include "fs_is_rofs.hpp"
 #include "fs_realpathize.hpp"
-#include "int_types.h"
+#include "base_types.h"
 #include "num.hpp"
 #include "str.hpp"
 #include "syslog.hpp"
@@ -81,9 +81,8 @@ namespace l
     u64 offset;
 
     offset = s_.find_first_not_of("+<>-=");
-    if (offset == std::string::npos) {
+    if(offset == std::string::npos)
       return;
-    }
 
     if(offset > 1)
       offset = 2;
@@ -154,6 +153,7 @@ namespace l
             rv = l::parse_minfreespace(v[1],minfreespace_);
             if(rv < 0)
               return rv;
+            [[fallthrough]];
           case 1:
             rv = l::parse_mode(v[0],mode_);
             if(rv < 0)

src/branches.hpp

@@ -30,6 +30,9 @@
 #include <vector>
 #include <memory>
 
+#define MINFREESPACE_DEFAULT (4294967295ULL)
+
+
 class Branches final : public ToFromString
 {
 public:
@@ -63,14 +66,18 @@ public:
 public:
   using Ptr = Branches::Impl::Ptr;
 
+public:
+  u64 minfreespace = MINFREESPACE_DEFAULT;
+
 private:
   mutable std::mutex _mutex;
   Ptr                _impl;
 
 public:
-  Branches(const u64 &default_minfreespace_)
-    : _impl(std::make_shared<Impl>(default_minfreespace_))
-  {}
+  Branches()
+    : _impl(std::make_shared<Impl>(minfreespace))
+  {
+  }
 
 public:
   int from_string(const std::string_view str) final;

src/caps.cpp

@@ -0,0 +1,104 @@
+#include "caps.hpp"
+
+#if defined __linux__
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/prctl.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/syscall.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <string.h>
+#include <grp.h>
+#include <linux/capability.h>
+#include <linux/securebits.h>
+
+
+static
+int
+capset(cap_user_header_t     header_,
+       const cap_user_data_t data_)
+{
+  return ::syscall(SYS_capset,header_,data_);
+}
+
+static
+int
+capget(cap_user_header_t header_,
+       cap_user_data_t   data_)
+{
+  return ::syscall(SYS_capget,header_,data_);
+}
+
+static
+int
+capset(int cap_bit_)
+{
+  int rv;
+  struct __user_cap_header_struct header;
+  struct __user_cap_data_struct data[2];
+
+  header.version = _LINUX_CAPABILITY_VERSION_3;
+  header.pid = 0;
+
+  rv = capget(&header,data);
+  if(rv < 0)
+    return rv;
+
+  int word = cap_bit_ / 32;
+  int bit  = cap_bit_ % 32;
+
+  data[word].permitted   |= (1 << bit);
+  data[word].effective   |= (1 << bit);
+  data[word].inheritable |= (1 << bit);
+
+  rv = capset(&header,data);
+  if(rv < 0)
+    return rv;
+
+  return 0;
+}
+
+int
+caps::setup()
+{
+  int rv;
+
+  rv = capset(CAP_DAC_OVERRIDE);
+  if(rv < 0)
+    return rv;
+  rv = capset(CAP_DAC_READ_SEARCH);
+  if(rv < 0)
+    return rv;
+  rv = capset(CAP_FOWNER);
+  if(rv < 0)
+    return rv;
+  rv = capset(CAP_CHOWN);
+  if(rv < 0)
+    return rv;
+  rv = capset(CAP_SETUID);
+  if(rv < 0)
+    return rv;
+  rv = capset(CAP_SETGID);
+  if(rv < 0)
+    return rv;
+
+  rv = prctl(PR_SET_SECUREBITS,
+             SECBIT_KEEP_CAPS | SECBIT_NO_SETUID_FIXUP);
+  if(rv < 0)
+    return -errno;
+
+  return 0;
+}
+#else
+#include <errno.h>
+
+int
+caps::setup()
+{
+  return -ENOSYS;
+}
+#endif

src/caps.hpp

@@ -0,0 +1,6 @@
+#pragma once
+
+namespace caps
+{
+  int setup();
+}

src/category.hpp

@@ -42,16 +42,8 @@ namespace Category
   public:
     Action(Funcs &funcs_)
     {
-      funcs.push_back(&funcs_.chmod);
-      funcs.push_back(&funcs_.chown);
       funcs.push_back(&funcs_.link);
-      funcs.push_back(&funcs_.removexattr);
       funcs.push_back(&funcs_.rename);
-      funcs.push_back(&funcs_.rmdir);
-      funcs.push_back(&funcs_.setxattr);
-      funcs.push_back(&funcs_.truncate);
-      funcs.push_back(&funcs_.unlink);
-      funcs.push_back(&funcs_.utimens);
     }
   };
 
@@ -78,12 +70,9 @@ namespace Category
   public:
     Search(Funcs &funcs_)
     {
-      funcs.push_back(&funcs_.access);
       funcs.push_back(&funcs_.getattr);
-      funcs.push_back(&funcs_.getxattr);
       funcs.push_back(&funcs_.listxattr);
       funcs.push_back(&funcs_.open);
-      funcs.push_back(&funcs_.readlink);
     }
   };
 }

src/config.cpp

@@ -37,7 +37,6 @@
 #include <sys/stat.h>
 #include <unistd.h>
 
-#define MINFREESPACE_DEFAULT (4294967295ULL)
 
 constexpr static const char CACHE_FILES_PROCESS_NAMES_DEFAULT[] =
   "rtorrent|"
@@ -79,9 +78,9 @@ Config::CfgConfigFile::to_string() const
 
 Config::Config()
   :
-  allow_idmap(false),
+  allow_idmap(true),
   async_read(true),
-  branches(minfreespace),
+  branches(),
   branches_mount_timeout(0),
   branches_mount_timeout_fail(false),
   cache_attr(1),
@@ -95,8 +94,6 @@ Config::Config()
   cache_writeback(false),
   category(func),
   config_file(),
-  congestion_threshold(fuse_cfg.congestion_threshold,0),
-  debug(fuse_cfg.debug,false),
   direct_io_allow_mmap(true),
   dropcacheonclose(false),
   export_support(true),
@@ -105,9 +102,6 @@ Config::Config()
   fsname(),
   func(),
   fuse_msg_size("1M"),
-  gid(fuse_cfg.gid,FUSE_CFG_INVALID_ID),
-  gid_cache_expire_timeout(60 * 60),
-  gid_cache_remove_timeout(60 * 60 * 12),
   handle_killpriv(true),
   handle_killpriv_v2(true),
   ignorepponrename(false),
@@ -117,40 +111,48 @@ Config::Config()
   link_cow(false),
   link_exdev(LinkEXDEV::ENUM::PASSTHROUGH),
   log_metrics(false),
-  max_background(fuse_cfg.max_background,0),
-  minfreespace(MINFREESPACE_DEFAULT),
+  minfreespace(branches.minfreespace),
   mountpoint(),
-  _mount(mountpoint),
-  _mountpoint(mountpoint),
   moveonenospc(true),
   nfsopenhack(NFSOpenHack::ENUM::OFF),
-  noforget(),
   nullrw(false),
   parallel_direct_writes(true),
   passthrough_io(PassthroughIO::ENUM::OFF),
-  passthrough_max_stack_depth(fuse_cfg.passthrough_max_stack_depth,1),
-  pin_threads(fuse_cfg.pin_threads,"false"),
+  passthrough_max_stack_depth(fuse_cfg.passthrough_max_stack_depth),
+  pin_threads(fuse_cfg.pin_threads),
   posix_acl(false),
-  process_thread_count(fuse_cfg.process_thread_count,-1),
-  process_thread_queue_depth(fuse_cfg.process_thread_queue_depth,2),
+  process_thread_count(fuse_cfg.process_thread_count),
+  process_thread_queue_depth(fuse_cfg.process_thread_queue_depth),
   proxy_ioprio(false),
-  read_thread_count(fuse_cfg.read_thread_count,0),
+  read_thread_count(fuse_cfg.read_thread_count),
   readahead(0),
   readdir("seq"),
-  remember_nodes(fuse_cfg.remember_nodes,0),
   rename_exdev(RenameEXDEV::ENUM::PASSTHROUGH),
   scheduling_priority(-10),
   security_capability(true),
-  srcmounts(branches),
   statfs(StatFS::ENUM::BASE),
   statfs_ignore(StatFSIgnore::ENUM::NONE),
   symlinkify(false),
   symlinkify_timeout(3600),
-  threads(fuse_cfg.read_thread_count),
-  uid(fuse_cfg.uid,FUSE_CFG_INVALID_ID),
-  umask(fuse_cfg.umask,FUSE_CFG_INVALID_UMASK),
-  version(MERGERFS_VERSION),
   xattr(XAttr::ENUM::PASSTHROUGH),
+
+  _congestion_threshold(fuse_cfg.congestion_threshold),
+  _debug(fuse_cfg.debug),
+  _getattr_statx(getattr,statx),
+  _gid(fuse_cfg.gid),
+  _max_background(fuse_cfg.max_background),
+  _mount(mountpoint),
+  _mountpoint(mountpoint),
+  _never_forget_nodes(),
+  _noforget(),
+  _remember(fuse_cfg.remember_nodes),
+  _remember_nodes(fuse_cfg.remember_nodes),
+  _srcmounts(branches),
+  _threads(fuse_cfg.read_thread_count),
+  _uid(fuse_cfg.uid),
+  _umask(fuse_cfg.umask),
+  _version(MERGERFS_VERSION),
+
   _initialized(false)
 {
   allow_idmap.ro =
@@ -159,7 +161,7 @@ Config::Config()
     branches_mount_timeout_fail.ro =
     cache_symlinks.ro =
     cache_writeback.ro =
-    congestion_threshold.ro =
+    _congestion_threshold.ro =
     direct_io_allow_mmap.ro =
     export_support.ro =
     fsname.ro =
@@ -167,26 +169,30 @@ Config::Config()
     handle_killpriv.ro =
     handle_killpriv_v2.ro =
     kernel_permissions_check.ro =
-    max_background.ro =
+    _max_background.ro =
     _mount.ro =
     _mountpoint.ro =
     nullrw.ro =
     pid.ro =
     pin_threads.ro =
+    posix_acl.ro =
     process_thread_count.ro =
     process_thread_queue_depth.ro =
     read_thread_count.ro =
     scheduling_priority.ro =
-    srcmounts.ro =
-    version.ro =
+    _srcmounts.ro =
+    _version.ro =
     true;
-  congestion_threshold.ro =
-    gid.display =
-    max_background.ro =
-    threads.display =
+  _congestion_threshold.display =
+    _gid.display =
+    _max_background.display =
     _mount.display =
-    uid.display =
-    umask.display =
+    _noforget.display =
+    _remember.display =
+    _srcmounts.display =
+    _threads.display =
+    _uid.display =
+    _umask.display =
     false;
 
   _map["allow-idmap"]                 = &allow_idmap;
@@ -211,61 +217,63 @@ Config::Config()
   _map["category.create"]             = &category.create;
   _map["category.search"]             = &category.search;
   _map["config"]                      = &config_file;
+  _map["debug"]                       = &_debug;
   _map["defaults"]                    = &_dummy;
-  _map["debug"]                       = &debug;
-  _map["direct-io-allow-mmap"]        = &direct_io_allow_mmap;
   _map["direct-io"]                   = &_dummy;
+  _map["direct-io-allow-mmap"]        = &direct_io_allow_mmap;
   _map["dropcacheonclose"]            = &dropcacheonclose;
   _map["export-support"]              = &export_support;
   _map["flush-on-close"]              = &flushonclose;
   _map["follow-symlinks"]             = &follow_symlinks;
   _map["fsname"]                      = &fsname;
-  _map["func.access"]                 = &func.access;
-  _map["func.chmod"]                  = &func.chmod;
-  _map["func.chown"]                  = &func.chown;
+  _map["func.access"]                 = &access;
+  _map["func.chmod"]                  = &chmod;
+  _map["func.chown"]                  = &chown;
   _map["func.create"]                 = &func.create;
-  _map["func.getattr"]                = &func.getattr;
-  _map["func.getxattr"]               = &func.getxattr;
+  _map["func.getattr"]                = &_getattr_statx;
+  _map["func.getxattr"]               = &getxattr;
   _map["func.link"]                   = &func.link;
-  _map["func.listxattr"]              = &func.listxattr;
+  _map["func.listxattr"]              = &listxattr;
   _map["func.mkdir"]                  = &func.mkdir;
-  _map["func.mknod"]                  = &func.mknod;
+  _map["func.mknod"]                  = &mknod;
   _map["func.open"]                   = &func.open;
   _map["func.readdir"]                = &readdir;
-  _map["func.readlink"]               = &func.readlink;
-  _map["func.removexattr"]            = &func.removexattr;
+  _map["func.readlink"]               = &readlink;
+  _map["func.removexattr"]            = &removexattr;
   _map["func.rename"]                 = &func.rename;
-  _map["func.rmdir"]                  = &func.rmdir;
-  _map["func.setxattr"]               = &func.setxattr;
+  _map["func.rmdir"]                  = &rmdir;
+  _map["func.setxattr"]               = &setxattr;
+  _map["func.statx"]                  = &_getattr_statx;
   _map["func.symlink"]                = &func.symlink;
-  _map["func.truncate"]               = &func.truncate;
-  _map["func.unlink"]                 = &func.unlink;
-  _map["func.utimens"]                = &func.utimens;
+  _map["func.truncate"]               = &truncate;
+  _map["func.unlink"]                 = &unlink;
+  _map["func.utimens"]                = &utimens;
   _map["fuse-msg-size"]               = &fuse_msg_size;
-  _map["gid"]                         = &gid;
-  _map["gid-cache.expire-timeout"]    = &gid_cache_expire_timeout;
-  _map["gid-cache.remove-timeout"]    = &gid_cache_remove_timeout;
+  _map["gid"]                         = &_gid;
+  _map["gid-cache.expire-timeout"]    = &_dummy;
+  _map["gid-cache.remove-timeout"]    = &_dummy;
   _map["handle-killpriv"]             = &handle_killpriv;
   _map["handle-killpriv-v2"]          = &handle_killpriv_v2;
   _map["hard-remove"]                 = &_dummy;
   _map["ignorepponrename"]            = &ignorepponrename;
   _map["inodecalc"]                   = &inodecalc;
-  _map["kernel-permissions-check"]    = &kernel_permissions_check;
   _map["kernel-cache"]                = &_dummy;
+  _map["kernel-permissions-check"]    = &kernel_permissions_check;
   _map["lazy-umount-mountpoint"]      = &lazy_umount_mountpoint;
-  _map["link-exdev"]                  = &link_exdev;
   _map["link-cow"]                    = &link_cow;
+  _map["link-exdev"]                  = &link_exdev;
   _map["log.metrics"]                 = &log_metrics;
   _map["minfreespace"]                = &minfreespace;
   _map["mount"]                       = &_mount;
   _map["mountpoint"]                  = &_mountpoint;
   _map["moveonenospc"]                = &moveonenospc;
   _map["negative-entry"]              = &_dummy;
+  _map["never-forget-nodes"]          = &_never_forget_nodes;
   _map["nfsopenhack"]                 = &nfsopenhack;
   _map["no-splice-move"]              = &_dummy;
   _map["no-splice-read"]              = &_dummy;
   _map["no-splice-write"]             = &_dummy;
-  _map["noforget"]                    = &noforget;
+  _map["noforget"]                    = &_noforget;
   _map["nonempty"]                    = &_dummy;
   _map["nullrw"]                      = &nullrw;
   _map["parallel-direct-writes"]      = &parallel_direct_writes;
@@ -279,23 +287,24 @@ Config::Config()
   _map["proxy-ioprio"]                = &proxy_ioprio;
   _map["read-thread-count"]           = &read_thread_count;
   _map["readahead"]                   = &readahead;
-  _map["remember-nodes"]              = &remember_nodes;
+  _map["remember"]                    = &_remember;
+  _map["remember-nodes"]              = &_remember_nodes;
   _map["rename-exdev"]                = &rename_exdev;
   _map["scheduling-priority"]         = &scheduling_priority;
   _map["security-capability"]         = &security_capability;
   _map["splice-move"]                 = &_dummy;
   _map["splice-read"]                 = &_dummy;
   _map["splice-write"]                = &_dummy;
-  _map["srcmounts"]                   = &srcmounts;
+  _map["srcmounts"]                   = &_srcmounts;
   _map["statfs"]                      = &statfs;
   _map["statfs-ignore"]               = &statfs_ignore;
   _map["symlinkify"]                  = &symlinkify;
   _map["symlinkify-timeout"]          = &symlinkify_timeout;
-  _map["threads"]                     = &threads;
-  _map["uid"]                         = &uid;
-  _map["umask"]                       = &umask;
+  _map["threads"]                     = &_threads;
+  _map["uid"]                         = &_uid;
+  _map["umask"]                       = &_umask;
   _map["use-ino"]                     = &_dummy;
-  _map["version"]                     = &version;
+  _map["version"]                     = &_version;
   _map["xattr"]                       = &xattr;
 }
 
@@ -371,7 +380,7 @@ Config::keys_listxattr(char   *list_,
       auto rv = fmt::format_to_n(list,size,
                                  "user.mergerfs.{}\0",
                                  key);
-      if(rv.out >= (list + size))
+      if(rv.out > (list + size))
         return -ERANGE;
       list += rv.size;
       size -= rv.size;
@@ -389,6 +398,7 @@ Config::get(const std::string &key_,
 
   key = str::replace(key_,'_','-');
 
+
   i = _map.find(key);
   if(i == _map.end())
     return -ENOATTR;
@@ -434,8 +444,6 @@ Config::from_stream(std::istream &istrm_)
 {
   int rv;
   std::string line;
-  std::string key;
-  std::string val;
   Config::ErrVec new_errs;
 
   while(std::getline(istrm_,line,'\n'))
@@ -444,13 +452,9 @@ Config::from_stream(std::istream &istrm_)
       if(line.empty() || (line[0] == '#'))
         continue;
 
-      str::splitkv(line,'=',&key,&val);
-      key = str::trim(key);
-      val = str::trim(val);
-
-      rv = set(key,val);
+      rv = set(line);
       if(rv < 0)
-        new_errs.push_back({-rv,key+'='+val});
+        new_errs.push_back({-rv,line});
     }
 
   rv = (new_errs.empty() ? 0 : -EINVAL);
@@ -552,6 +556,9 @@ Config::Err::to_string() const
     case ELOOP:
       s = "too many levels of config";
       break;
+    case ENOENT:
+      s = "no value set";
+      break;
     default:
       s = strerror(err);
       break;

src/config.hpp

@@ -16,13 +16,29 @@
 
 #pragma once
 
+#include "func_access.hpp"
+#include "func_chmod.hpp"
+#include "func_chown.hpp"
+#include "func_getattr.hpp"
+#include "func_getxattr.hpp"
+#include "func_listxattr.hpp"
+#include "func_mknod.hpp"
+#include "func_readlink.hpp"
+#include "func_removexattr.hpp"
+#include "func_rmdir.hpp"
+#include "func_setxattr.hpp"
+#include "func_statx.hpp"
+#include "func_truncate.hpp"
+#include "func_unlink.hpp"
+#include "func_utimens.hpp"
+
 #include "branches.hpp"
 #include "category.hpp"
 #include "config_cachefiles.hpp"
 #include "config_dummy.hpp"
 #include "config_flushonclose.hpp"
 #include "config_follow_symlinks.hpp"
-#include "config_gidcache.hpp"
+#include "config_getattr_statx.hpp"
 #include "config_inodecalc.hpp"
 #include "config_link_exdev.hpp"
 #include "config_log_metrics.hpp"
@@ -109,6 +125,22 @@ public:
   Config& operator=(const Config&);
 
 public:
+  Func2::Access      access{"all"};
+  Func2::Chmod       chmod{"all"};
+  Func2::Chown       chown{"all"};
+  Func2::GetAttr     getattr{"cdfo"};
+  Func2::Getxattr    getxattr{"ff"};
+  Func2::Listxattr   listxattr{"ff"};
+  Func2::Mknod       mknod{"ff"};
+  Func2::Readlink    readlink{"ff"};
+  Func2::Removexattr removexattr{"all"};
+  Func2::Rmdir       rmdir{"all"};
+  Func2::Setxattr    setxattr{"all"};
+  Func2::Statx       statx{"cdfo"};
+  Func2::Truncate    truncate{"all"};
+  Func2::Unlink      unlink{"all"};
+  Func2::Utimens     utimens{"all"};
+
   ConfigBOOL     allow_idmap;
   ConfigBOOL     async_read;
   Branches       branches;
@@ -125,8 +157,6 @@ public:
   ConfigBOOL     cache_writeback;
   Categories     category;
   CfgConfigFile  config_file;
-  TFSRef<int>    congestion_threshold;
-  TFSRef<bool>   debug;
   ConfigBOOL     direct_io_allow_mmap;
   ConfigBOOL     dropcacheonclose;
   ConfigBOOL     export_support;
@@ -135,9 +165,6 @@ public:
   ConfigSTR      fsname;
   Funcs          func;
   ConfigPageSize fuse_msg_size;
-  TFSRef<s64>    gid;
-  GIDCacheExpireTimeout gid_cache_expire_timeout;
-  GIDCacheRemoveTimeout gid_cache_remove_timeout;
   ConfigBOOL     handle_killpriv;
   ConfigBOOL     handle_killpriv_v2;
   ConfigBOOL     ignorepponrename;
@@ -147,14 +174,10 @@ public:
   ConfigBOOL     link_cow;
   LinkEXDEV      link_exdev;
   LogMetrics     log_metrics;
-  TFSRef<int>    max_background;
-  ConfigUINT64   minfreespace;
+  TFSRef<u64>    minfreespace;
   fs::path       mountpoint;
-  TFSRef<fs::path> _mount;
-  TFSRef<fs::path> _mountpoint;
   MoveOnENOSPC   moveonenospc;
   NFSOpenHack    nfsopenhack;
-  CfgNoforget    noforget;
   ConfigBOOL     nullrw;
   ConfigBOOL     parallel_direct_writes;
   PassthroughIO  passthrough_io;
@@ -168,23 +191,33 @@ public:
   TFSRef<int>    read_thread_count;
   ConfigUINT64   readahead;
   FUSE::ReadDir  readdir;
-  TFSRef<s64>    remember_nodes;
   RenameEXDEV    rename_exdev;
   ConfigINT      scheduling_priority;
   ConfigBOOL     security_capability;
-  SrcMounts      srcmounts;
   StatFS         statfs;
   StatFSIgnore   statfs_ignore;
   ConfigBOOL     symlinkify;
   ConfigS64      symlinkify_timeout;
-  TFSRef<int>    threads;
-  TFSRef<s64>    uid;
-  TFSRef<s64>    umask;
-  ConfigROSTR    version;
   XAttr          xattr;
 
 private:
-  CfgDummy _dummy;
+  TFSRef<int>      _congestion_threshold;
+  TFSRef<bool>     _debug;
+  CfgDummy         _dummy;
+  ConfigGetAttrStatx _getattr_statx;
+  TFSRef<s64>      _gid;
+  TFSRef<int>      _max_background;
+  TFSRef<fs::path> _mount;
+  TFSRef<fs::path> _mountpoint;
+  CfgNoforget      _never_forget_nodes;
+  CfgNoforget      _noforget;
+  TFSRef<s64>      _remember;
+  TFSRef<s64>      _remember_nodes;
+  SrcMounts        _srcmounts;
+  TFSRef<int>      _threads;
+  TFSRef<s64>      _uid;
+  TFSRef<s64>      _umask;
+  ConfigROSTR      _version;
 
 private:
   bool _initialized;

src/config_follow_symlinks.hpp

@@ -19,12 +19,6 @@
 #pragma once
 
 #include "enum.hpp"
+#include "follow_symlinks_enum.hpp"
 
-enum class FollowSymlinksEnum
-  {
-    NEVER,
-    DIRECTORY,
-    REGULAR,
-    ALL
-  };
 typedef Enum<FollowSymlinksEnum> FollowSymlinks;

src/config_getattr_statx.hpp

@@ -0,0 +1,41 @@
+#pragma once
+
+#include "config.hpp"
+#include "tofrom_string.hpp"
+
+class ConfigGetAttrStatx : public ToFromString
+{
+private:
+  Func2::GetAttr &_getattr;
+  Func2::Statx   &_statx;
+
+public:
+  ConfigGetAttrStatx() = delete;
+  ConfigGetAttrStatx(Func2::GetAttr &getattr_,
+                     Func2::Statx   &statx_)
+    : _getattr(getattr_),
+      _statx(statx_)
+  {
+  }
+
+  std::string
+  to_string() const
+  {
+    return _getattr.to_string();
+  }
+
+  int
+  from_string(const std::string_view str_)
+  {
+    int rv;
+
+    rv = _getattr.from_string(str_);
+    if(rv < 0)
+      return rv;
+
+    rv = _statx.from_string(str_);
+    assert(rv == 0);
+
+    return rv;
+  }
+};

src/config_gidcache.cpp

@@ -1,65 +0,0 @@
-#include "config_gidcache.hpp"
-
-#include "gidcache.hpp"
-
-#include "to_string.hpp"
-#include "from_string.hpp"
-
-
-GIDCacheExpireTimeout::GIDCacheExpireTimeout(const int i_)
-{
-  GIDCache::expire_timeout = i_;
-}
-
-GIDCacheExpireTimeout::GIDCacheExpireTimeout(const std::string &s_)
-{
-  from_string(s_);
-}
-
-std::string
-GIDCacheExpireTimeout::to_string(void) const
-{
-  return str::to(GIDCache::expire_timeout);
-}
-
-int
-GIDCacheExpireTimeout::from_string(const std::string_view s_)
-{
-  int rv;
-
-  rv = str::from(s_,&GIDCache::expire_timeout);
-  if(rv < 0)
-    return rv;
-
-  return 0;
-}
-
-
-GIDCacheRemoveTimeout::GIDCacheRemoveTimeout(const int i_)
-{
-  GIDCache::remove_timeout = i_;
-}
-
-
-GIDCacheRemoveTimeout::GIDCacheRemoveTimeout(const std::string &s_)
-{
-  from_string(s_);
-}
-
-std::string
-GIDCacheRemoveTimeout::to_string(void) const
-{
-  return str::to(GIDCache::remove_timeout);
-}
-
-int
-GIDCacheRemoveTimeout::from_string(const std::string_view s_)
-{
-  int rv;
-
-  rv = str::from(s_,&GIDCache::remove_timeout);
-  if(rv < 0)
-    return rv;
-
-  return 0;
-}

src/config_gidcache.hpp

@@ -1,25 +0,0 @@
-#pragma once
-
-#include "tofrom_string.hpp"
-
-class GIDCacheExpireTimeout : public ToFromString
-{
-public:
-  GIDCacheExpireTimeout(const int i = 60 * 60);
-  GIDCacheExpireTimeout(const std::string &);
-
-public:
-  std::string to_string(void) const final;
-  int from_string(const std::string_view) final;
-};
-
-class GIDCacheRemoveTimeout : public ToFromString
-{
-public:
-  GIDCacheRemoveTimeout(const int = 60 * 60 * 12);
-  GIDCacheRemoveTimeout(const std::string &);
-
-public:
-  std::string to_string(void) const final;
-  int from_string(const std::string_view) final;
-};

src/config_pagesize.hpp

@@ -44,7 +44,7 @@ public:
     return *this;
   }
 
-  operator const uint64_t() const
+  operator uint64_t() const
   {
     return _v;
   }

src/dirinfo.hpp

@@ -18,7 +18,7 @@
 
 #include "fh.hpp"
 
-#include "int_types.h"
+#include "base_types.h"
 
 
 class DirInfo : public FH

src/error.hpp

@@ -15,27 +15,34 @@ public:
   {
   }
 
-  operator int()
+  operator int() const
   {
-    return (_err.has_value() ? _err.value() : -ENOENT);
+    return (_err.has_value() ? _err.value() : 0);
   }
 
+  // A rough heuristic for prioritizing errors. Success always
+  // overrides failures. ENOENT is lowest errno priority, then EROFS
+  // (which can be set due to branch mode = RO) then any other error.
   Err&
-  operator=(int v_)
+  operator=(int new_err_)
   {
     if(!_err.has_value())
-      _err = ((v_ >= 0) ? 0 : v_);
-    else if(v_ >= 0)
+      _err = ((new_err_ >= 0) ? 0 : new_err_);
+    else if(new_err_ >= 0)
       _err = 0;
+    else if(_err == -ENOENT)
+      _err = new_err_;
+    else if((_err == -EROFS) && (new_err_ != -ENOENT))
+      _err = new_err_;
 
     return *this;
   }
 
   bool
-  operator==(int v_)
+  operator==(int other_)
   {
     if(_err.has_value())
-      return (_err.value() == v_);
+      return (_err.value() == other_);
     return false;
   }
 };

src/fileinfo.hpp

@@ -20,9 +20,9 @@
 #include "fh.hpp"
 #include "fs_path.hpp"
 
-#include <mutex>
+#include "base_types.h"
 
-#include "int_types.h"
+#include <mutex>
 
 
 class FileInfo : public FH

src/follow_symlinks_enum.hpp

@@ -0,0 +1,9 @@
+#pragma once
+
+enum class FollowSymlinksEnum
+  {
+    NEVER,
+    DIRECTORY,
+    REGULAR,
+    ALL
+  };

src/from_string.cpp

@@ -31,11 +31,13 @@ str::from(const std::string_view  value_,
           bool                   *bool_)
 {
   if((value_ == "true") ||
+     (value_ == "t")    ||
      (value_ == "1")    ||
      (value_ == "on")   ||
      (value_ == "yes"))
     *bool_ = true;
   ef((value_ == "false") ||
+     (value_ == "f")     ||
      (value_ == "0")     ||
      (value_ == "off")   ||
      (value_ == "no"))

src/fs_attr.hpp

@@ -18,7 +18,7 @@
 
 #include <string>
 
-#include "int_types.h"
+#include "base_types.h"
 
 #define FS_ATTR_NONE (0)
 #define FS_ATTR_CLEAR_IMMUTABLE (1 << 0)

src/fs_attr_linux.icpp

@@ -31,7 +31,7 @@ using std::string;
 static
 int
 _get_fs_ioc_flags(const int  fd,
-                 int       &flags)
+                  int       &flags)
 {
   int rv;
 
@@ -45,7 +45,7 @@ _get_fs_ioc_flags(const int  fd,
 static
 int
 _get_fs_ioc_flags(const string &file,
-                 int          &flags)
+                  int          &flags)
 {
   int fd;
   int rv;

src/fs_clonepath.cpp

@@ -27,6 +27,16 @@
 #include "fs_xattr.hpp"
 #include "ugid.hpp"
 
+#include "fs_close.hpp"
+#include "fs_fstat.hpp"
+#include "fs_mkdirat.hpp"
+#include "fs_openat.hpp"
+#include "fs_fchown.hpp"
+#include "fs_fchmod.hpp"
+#include "fs_futimens.hpp"
+
+#include "scope_guard.hpp"
+
 
 static
 bool
@@ -107,21 +117,62 @@ fs::clonepath(const fs::path &srcpath_,
   return 0;
 }
 
+
+// WORK IN PROGRESS
+static
 int
-fs::clonepath_as_root(const fs::path &srcpath_,
-                      const fs::path &dstpath_,
-                      const fs::path &relpath_,
-                      const bool      return_metadata_errors_)
+_clonepath2(const int       srcfd_,
+            const int       dstfd_,
+            const fs::path &dirname_,
+            const bool      return_metadata_errors_)
 {
-  if(relpath_.empty())
-    return 0;
-  if(srcpath_ == dstpath_)
+  int rv;
+  int srcdirfd;
+  int dstdirfd;
+  struct stat st;
+
+  if(dirname_.empty())
     return 0;
 
-  const ugid::SetRootGuard ugid_guard;
+  rv = fs::mkdirat(dstfd_,dirname_,0);
+  if(rv < 0)
+    return ((rv == -EEXIST) ? 0 : rv);
 
-  return fs::clonepath(srcpath_,
-                       dstpath_,
-                       relpath_,
-                       return_metadata_errors_);
+  srcdirfd = fs::openat(srcfd_,dirname_,O_DIRECTORY);
+  if(srcdirfd < 0)
+    return srcdirfd;
+  DEFER { fs::close(srcdirfd); };
+
+  dstdirfd = fs::openat(dstfd_,dirname_,O_DIRECTORY);
+  if(dstdirfd < 0)
+    return dstdirfd;
+  DEFER { fs::close(dstdirfd); };
+
+  rv = fs::attr::copy(srcdirfd,dstdirfd,FS_ATTR_CLEAR_IMMUTABLE);
+  if(return_metadata_errors_ && (rv < 0) && !::_ignorable_error(-rv))
+    return rv;
+
+  rv = fs::xattr::copy(srcdirfd,dstdirfd);
+  if(return_metadata_errors_ && (rv < 0) && !::_ignorable_error(-rv))
+    return rv;
+
+  rv = fs::fstat(srcdirfd,&st);
+  if(rv < 0)
+    return rv;
+  if(!S_ISDIR(st.st_mode))
+    return -ENOTDIR;
+
+  rv = fs::fchown_check_on_error(dstdirfd,st);
+  if(rv < 0)
+    return rv;
+
+  rv = fs::fchmod_check_on_error(dstdirfd,st);
+  if(rv < 0)
+    return rv;
+
+  rv = fs::futimens(dstdirfd,st);
+  if(rv < 0)
+    return rv;
+
+  return 0;
 }

src/fs_clonepath.hpp

@@ -25,9 +25,4 @@ namespace fs
                 const fs::path &dstpath,
                 const fs::path &relpath,
                 const bool      return_metadata_errors = false);
-
-  int clonepath_as_root(const fs::path &srcpath,
-                        const fs::path &dstpath,
-                        const fs::path &relpath,
-                        const bool      return_metadata_errors = false);
 }

src/fs_copydata.hpp

@@ -18,7 +18,7 @@
 
 #pragma once
 
-#include "int_types.h"
+#include "base_types.h"
 
 
 namespace fs

src/fs_copydata_copy_file_range.cpp

@@ -20,7 +20,7 @@
 #include "fs_copy_file_range.hpp"
 #include "fs_fstat.hpp"
 
-#include "int_types.h"
+#include "base_types.h"
 
 
 static

src/fs_copydata_copy_file_range.hpp

@@ -16,7 +16,7 @@
 
 #pragma once
 
-#include "int_types.h"
+#include "base_types.h"
 
 
 namespace fs

src/fs_copydata_readwrite.hpp

@@ -16,7 +16,7 @@
 
 #pragma once
 
-#include "int_types.h"
+#include "base_types.h"
 
 namespace fs
 {

src/fs_copyfile.cpp

@@ -103,7 +103,7 @@ fs::copyfile(const int                src_fd_,
 {
   s64 rv;
   int dst_fd;
-  struct stat src_st = {0};
+  struct stat src_st = {};
   std::string dst_tmppath;
   struct sigaction old_act;
   struct sigaction new_act;

src/fs_copyfile.hpp

@@ -1,6 +1,6 @@
 #pragma once
 
-#include "int_types.h"
+#include "base_types.h"
 #include "fs_path.hpp"
 
 #include <sys/stat.h>

src/fs_glob.cpp

@@ -38,7 +38,7 @@ fs::glob(const string   &pattern_,
          vector<string> *strs_)
 {
   int flags;
-  glob_t gbuf = {0};
+  glob_t gbuf = {};
 
   flags = (GLOB_BRACE|GLOB_ONLYDIR);
   ::glob(pattern_.c_str(),flags,NULL,&gbuf);

src/fs_is_rofs.hpp

@@ -49,8 +49,6 @@ namespace fs
   bool
   is_rofs(const fs::path &path_)
   {
-    ugid::SetRootGuard const ugid;
-
     int fd;
     std::string tmp_filepath;
 

src/fs_lstat.hpp

@@ -19,8 +19,7 @@
 #pragma once
 
 #include "to_neg_errno.hpp"
-
-#include <string>
+#include "to_cstr.hpp"
 
 #include <sys/stat.h>
 #include <sys/types.h>
@@ -29,25 +28,17 @@
 
 namespace fs
 {
+  template<typename PathType>
   static
   inline
   int
-  lstat(const char  *path_,
-        struct stat *st_)
+  lstat(const PathType &path_,
+        struct stat    *st_)
   {
     int rv;
 
-    rv = ::lstat(path_,st_);
+    rv = ::lstat(to_cstr(path_),st_);
 
     return ::to_neg_errno(rv);
   }
-
-  static
-  inline
-  int
-  lstat(const std::string &path_,
-        struct stat       *st_)
-  {
-    return fs::lstat(path_.c_str(),st_);
-  }
 }

src/fs_mkdir_as.hpp

@@ -0,0 +1,49 @@
+#pragma once
+
+#include "fs_mkdir.hpp"
+#include "ugid.hpp"
+
+
+#if defined __linux__
+namespace fs
+{
+  template<typename T>
+  static
+  inline
+  int
+  mkdir_as(const ugid_t  ugid_,
+           const T      &path_,
+           const mode_t  mode_)
+  {
+    const ugid::SetGuard _(ugid_);
+
+    return fs::mkdir(path_,mode_);
+  }
+}
+#elif defined __FreeBSD__
+#include "fs_lchown.hpp"
+
+namespace fs
+{
+  template<typename T>
+  static
+  inline
+  int
+  mkdir_as(const ugid_t  ugid_,
+           const T      &path_,
+           const mode_t  mode_)
+  {
+    int rv;
+
+    rv = fs::mkdir(path_,mode_);
+    if(rv < 0)
+      return rv;
+
+    fs::lchown(path_,ugid_.uid,ugid_.gid);
+
+    return 0;
+  }
+}
+#else
+#error "Not Supported"
+#endif

src/fs_mkdir_as_root.hpp

@@ -1,35 +0,0 @@
-/*
-  ISC License
-
-  Copyright (c) 2021, Antonio SJ Musumeci <trapexit@spawn.link>
-
-  Permission to use, copy, modify, and/or distribute this software for any
-  purpose with or without fee is hereby granted, provided that the above
-  copyright notice and this permission notice appear in all copies.
-
-  THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
-  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
-  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
-  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
-  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
-  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
-  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
-*/
-
-#include "fs_mkdir.hpp"
-#include "ugid.hpp"
-
-namespace fs
-{
-  template<typename T>
-  static
-  inline
-  int
-  mkdir_as_root(const T      &path_,
-                const mode_t  mode_)
-  {
-    const ugid::SetRootGuard guard;
-
-    return fs::mkdir(path_,mode_);
-  }
-}

src/fs_mkdirat.hpp

@@ -0,0 +1,48 @@
+#pragma once
+
+#include "to_neg_errno.hpp"
+#include "fs_path.hpp"
+
+#include <fcntl.h>
+#include <sys/stat.h>
+
+namespace fs
+{
+  static
+  inline
+  int
+  mkdirat(const int     dirfd_,
+          const char   *pathname_,
+          const mode_t  mode_)
+  {
+    int rv;
+
+    rv = ::mkdirat(dirfd_,pathname_,mode_);
+
+    return ::to_neg_errno(rv);
+  }
+
+  static
+  inline
+  int
+  mkdirat(const int          dirfd_,
+          const std::string &pathname_,
+          const mode_t       mode_)
+  {
+    return fs::mkdirat(dirfd_,
+                       pathname_.c_str(),
+                       mode_);
+  }
+
+  static
+  inline
+  int
+  mkdirat(const int       dirfd_,
+          const fs::path &pathname_,
+          const mode_t    mode_)
+  {
+    return fs::mkdirat(dirfd_,
+                       pathname_.c_str(),
+                       mode_);
+  }
+}

src/fs_mknod_as.hpp

@@ -0,0 +1,58 @@
+#pragma once
+
+#include "fs_acl.hpp"
+#include "fs_mknod.hpp"
+#include "ugid.hpp"
+
+
+#if defined __linux__
+namespace fs
+{
+  template<typename T>
+  static
+  inline
+  int
+  mknod_as(const ugid_t  ugid_,
+           const T      &path_,
+           mode_t        mode_,
+           dev_t         dev_,
+           mode_t        umask_)
+  {
+    if(not fs::acl::dir_has_defaults(path_))
+      mode_ &= ~umask_;
+
+    const ugid::SetGuard _(ugid_);
+
+    return fs::mknod(path_,mode_,dev_);
+  }
+}
+#elif defined __FreeBSD__
+#include "fs_lchown.hpp"
+
+namespace fs
+{
+  template<typename T>
+  static
+  inline
+  int
+  mknod_as(const ugid_t  ugid_,
+           const T      &path_,
+           mode_t        mode_,
+           dev_t         dev_,
+           mode_t        umask_)
+  {
+    int rv;
+
+    if(not fs::acl::dir_has_defaults(path_))
+      mode_ &= ~umask_;
+
+    rv = fs::mknod(path_,mode_,dev_);
+
+    fs::lchown(path_,ugid_.uid,ugid_.gid);
+
+    return rv;
+  }
+}
+#else
+#error "Not Supported!"
+#endif

src/fs_movefile_and_open.cpp

@@ -16,6 +16,7 @@
 
 #include "fs_movefile_and_open.hpp"
 
+#include "base_types.h"
 #include "errno.hpp"
 #include "fs_clonepath.hpp"
 #include "fs_close.hpp"
@@ -30,7 +31,6 @@
 #include "fs_rename.hpp"
 #include "fs_stat.hpp"
 #include "fs_unlink.hpp"
-#include "int_types.h"
 #include "policy.hpp"
 #include "ugid.hpp"
 
@@ -137,8 +137,6 @@ fs::movefile_and_open_as_root(const Policy::Create &policy_,
                               const fs::path       &fusepath_,
                               const int             origfd_)
 {
-  const ugid::Set ugid(0,0);
-
   return fs::movefile_and_open(policy_,
                                branches_,
                                branchpath_,

src/fs_open_as.hpp

@@ -0,0 +1,56 @@
+#pragma once
+
+#include "fs_open.hpp"
+#include "ugid.hpp"
+
+// Linux can set ugid because it allows for credentials per
+// thread. FreeBSD however does not and must create as root then
+// chown. Another option for both platforms would be to create a temp
+// file, chown, then rename to target. Unfortunately, depending on if
+// the target filesystem is POSIX compliant or uses POSIX / extended
+// ACLs it is not possible to know what is best.
+
+
+#if defined __linux__
+namespace fs
+{
+  static
+  inline
+  int
+  open_as(const ugid_t    ugid_,
+          const fs::path &path_,
+          const int       flags_,
+          const mode_t    mode_)
+  {
+    const ugid::SetGuard _(ugid_);
+
+    return fs::open(path_,flags_,mode_);
+  }
+}
+#elif defined __FreeBSD__
+#include "fs_fchown.hpp"
+
+namespace fs
+{
+  static
+  inline
+  int
+  open_as(const ugid_t    ugid_,
+          const fs::path &path_,
+          const int       flags_,
+          const mode_t    mode_)
+  {
+    int rv;
+
+    rv = fs::open(path_,flags_,mode_);
+    if(rv < 0)
+      return rv;
+
+    fs::fchown(rv,ugid_.uid,ugid_.gid);
+
+    return rv;
+  }
+}
+#else
+#error "Not Supported!"
+#endif

src/fs_pread.hpp

@@ -18,7 +18,7 @@
 
 #pragma once
 
-#include "int_types.h"
+#include "base_types.h"
 #include "to_neg_errno.hpp"
 
 #include <unistd.h>

src/fs_stat.hpp

@@ -18,7 +18,10 @@
 
 #pragma once
 
+#include "follow_symlinks_enum.hpp"
 #include "to_neg_errno.hpp"
+#include "to_cstr.hpp"
+#include "fs_lstat.hpp"
 
 #include <string>
 
@@ -29,25 +32,71 @@
 
 namespace fs
 {
+  template<typename PathType>
   static
   inline
   int
-  stat(const char  *path_,
-       struct stat *st_)
+  stat(const PathType &path_,
+       struct stat    *st_)
   {
     int rv;
 
-    rv = ::stat(path_,st_);
+    rv = ::stat(to_cstr(path_),st_);
 
     return ::to_neg_errno(rv);
   }
 
+  template<typename PathType>
   static
   inline
   int
-  stat(const std::string &path_,
-       struct stat       *st_)
+  stat(const PathType     &path_,
+       struct stat        *st_,
+       FollowSymlinksEnum  follow_)
   {
-    return fs::stat(path_.c_str(),st_);
+    int rv;
+
+    switch(follow_)
+      {
+      default:
+      case FollowSymlinksEnum::NEVER:
+        rv = fs::lstat(path_,st_);
+        return rv;
+      case FollowSymlinksEnum::DIRECTORY:
+        rv = fs::lstat(path_,st_);
+        if((rv >= 0) && S_ISLNK(st_->st_mode))
+          {
+            struct stat st;
+
+            rv = fs::stat(path_,&st);
+            if(rv < 0)
+              return rv;
+
+            if(S_ISDIR(st.st_mode))
+              *st_ = st;
+          }
+        return rv;
+      case FollowSymlinksEnum::REGULAR:
+        rv = fs::lstat(path_,st_);
+        if((rv >= 0) && S_ISLNK(st_->st_mode))
+          {
+            struct stat st;
+
+            rv = fs::stat(path_,&st);
+            if(rv < 0)
+              return rv;
+
+            if(S_ISREG(st.st_mode))
+              *st_ = st;
+          }
+        return rv;
+      case FollowSymlinksEnum::ALL:
+        rv = fs::stat(path_,st_);
+        if(rv < 0)
+          rv = fs::lstat(path_,st_);
+        return rv;
+      }
+
+    return -ENOENT;
   }
 }